FIFTH AMENDED AND RESTATED
 
                          CERTIFICATE OF INCORPORATION
 
                                       OF
 
                                  VIACELL, INC.
 
                     Pursuant to Section 242 and 245 of the
                General Corporation Law of the State of Delaware
 
      The undersigned, for the purpose of amending and restating the Amended and
Restated Certificate of Incorporation of ViaCell, Inc. (the "Corporation"), as
amended and supplemented heretofore under the laws of the State of Delaware
hereby certifies as follows:
 
            1. The corporation was incorporated in the State of Delaware on
September 2, 1994 under the name "t. Breeders, Inc."
 
            2. Pursuant to an Amended and Restated Certificate of Incorporation,
dated April 11, 2000, the name of the Corporation was changed to ViaCell, Inc.
 
            3. Pursuant to a unanimous written consent of the Board of Directors
of the Corporation, a resolution was duly adopted pursuant to Section 242 and
245 of the General Corporation Law of the State of Delaware, setting forth this
Fifth Amended and Restated Certificate of Incorporation and declaring said Fifth
Amended and Restated Certificate to be advisable. The stockholders of the
Corporation duly approved said proposed Fifth Amended and Restated Certificate
by written consent in accordance with Sections 228, 242 and 245 of the General
Corporation Law of the State of Delaware, and written notice of such consent has
been given to all stockholders who have not consented in writing to said Fifth
Amended and Restated Certificate.
 
            4. This Fifth Amended and Restated Certificate of Incorporation of
ViaCell, Inc. (this "Certificate") amends and restates the Fourth Amended and
Restated Certificate of Incorporation in its entirety as follows:
 
      FIRST. The name of the corporation is ViaCell, Inc. (the "Corporation")
 
      SECOND. The address of the Corporation's registered office in the State of
Delaware is 1209 Orange Street, Wilmington, County of New Castle, Delaware
19801. The name of its registered agent at such address is The Corporation Trust
Company.
 
      THIRD. The purpose of the Corporation is to engage in any lawful act or
activity for which corporations may be organized under the General Corporation
Law of Delaware.
 
      FOURTH. The total number of shares of all classes of stock which the
Corporation shall have authority to issue is (i) 80,000,000 shares of Common
Stock, $.01 par value per share ("Common Stock") and (ii) 30,825,000 shares of
Preferred Stock, $.01 par value per share ("Preferred Stock"), of which 100,000
shares shall be designated "Series A Convertible Preferred
 
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Stock" (the "Series A Preferred Stock"), 82,857 shares shall be designated
"Series B Convertible Preferred Stock" (the "Series B Preferred Stock"), 919,220
shares shall be designated "Series C Convertible Preferred Stock" (the "Series C
Preferred Stock"), 1,500,000 shares shall be designated "Series D Convertible
Preferred Stock" (the "Series D Preferred Stock"), 1,983,334 shares shall be
designated "Series E Convertible Preferred Stock" (the "Series E Preferred
Stock"), 2,666,666 shares shall be designated "Series F Convertible Preferred
Stock" (the "Series F Preferred Stock"), 3,666,667 shares shall be designated
"Series G Convertible Preferred Stock" (the "Series G Preferred Stock"),
7,577,334 shares shall be designated "Series H Convertible Preferred Stock" (the
"Series H Preferred Stock"), 5,575,000 shares shall be designated "Series I
Convertible Preferred Stock" (the "Series I Preferred Stock"), 3,750,000 shares
shall be designated "Series J Convertible Preferred Stock" (the "Series J
Preferred Stock") and 2,500,000 shares shall be designated "Series K Convertible
Preferred Stock" (the "Series K Preferred Stock"). The term "Designated
Preferred Stock" used without reference to the Series A Preferred Stock, the
Series B Preferred Stock, the Series C Preferred Stock, the Series D Preferred
Stock, the Series E Preferred Stock, the Series F Preferred Stock, the Series G
Preferred Stock, Series H Preferred Stock, Series I Preferred Stock, Series J
Preferred Stock and Series K Preferred Stock means all of the Series A Preferred
Stock, Series B Preferred Stock, Series C Preferred Stock, Series D Preferred
Stock, Series E Preferred Stock, the Series F Preferred Stock, the Series G
Preferred Stock, Series H Preferred Stock, Series I Preferred Stock, Series J
Preferred Stock and Series K Preferred Stock share for share alike without
distinction as to series except as otherwise expressly provided or as the
context otherwise requires.
 
      The following is a statement of the designations and the powers,
privileges and rights, and the qualifications, limitations or restrictions
thereof in respect of each class of capital stock of the Corporation.
 
A.    COMMON STOCK.
 
      1. General. The voting, dividend and liquidation rights of the holders of
the Common Stock are subject to and qualified by the rights of the holders of
the Preferred Stock of any series as may be designated by the Board of Directors
upon any issuance of the Preferred Stock of any series.
 
      2. Voting. The holders of the Common Stock are entitled to one vote for
each share held at all meetings of stockholders (and written actions in lieu of
meetings). There shall be no cumulative voting.
 
      The number of authorized shares of Common Stock may be increased or
decreased (but not below the number of shares thereof then outstanding) by the
affirmative vote of the holders of a majority of the stock of the Corporation
entitled to vote, irrespective of the provisions of Section 242(b)(2) of the
General Corporation Law of Delaware.
 
      3. Dividends. Dividends may be declared and paid on the Common Stock from
funds lawfully available therefor as and when determined by the Board of
Directors and subject to any preferential dividend rights of any then
outstanding Preferred Stock.
 
 
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      4. Liquidation. Upon the dissolution or liquidation of the Corporation,
whether voluntary or involuntary, holders of Common Stock will be entitled to
receive all assets of the Corporation available for distribution to its
stockholders, subject to any preferential rights of any then outstanding
Preferred Stock.
 
B.    PREFERRED STOCK.
 
      Preferred Stock may be issued from time to time in one or more series,
each of such series to have such terms as stated or expressed herein and in the
resolution or resolutions providing for the issue of such series adopted by the
Board of Directors of the Corporation as hereinafter provided. Any shares of
Preferred Stock which may be redeemed, purchased or acquired by the Corporation
may be reissued except as otherwise provided by law. Different series of
Preferred Stock shall not be construed to constitute different classes of shares
for the purposes of voting by classes unless expressly provided.
 
      Authority is hereby expressly granted to the Board of Directors from time
to time to issue the Preferred Stock in one or more series, and in connection
with the creation of any such series, by resolution or resolutions providing for
the issue of the shares thereof, to determine and fix such voting powers, full
or limited, or no voting powers, and such designations, preferences and relative
participating, optional or other special rights, and qualifications, limitations
or restrictions thereof, including without limitation thereof, dividend rights,
special voting rights, conversion rights, redemption privileges and liquidation
preferences, as shall be stated and expressed in such resolutions, all to the
full extent now or hereafter permitted by the General Corporation Law of
Delaware. Without limiting the generality of the foregoing, the resolutions
providing for issuance of any series of Preferred Stock may provide that such
Series shall rank equally or be junior to outstanding Preferred Stock of any
other Series to the extent permitted by law. Except as otherwise specifically
provided in this Certificate, no vote of the holders of the Preferred Stock or
Common Stock shall be a prerequisite to the issuance of any shares of any series
of the Preferred Stock authorized by and complying with the conditions of this
Certificate, the right to have such vote being expressly waived by all present
and future holders of the capital stock of the Corporation.
 
C.    DESCRIPTION AND DESIGNATION OF SERIES A CONVERTIBLE PREFERRED STOCK,
      SERIES B CONVERTIBLE PREFERRED STOCK, SERIES C CONVERTIBLE PREFERRED
      STOCK, SERIES D CONVERTIBLE PREFERRED STOCK, SERIES E CONVERTIBLE
      PREFERRED STOCK, SERIES F CONVERTIBLE PREFERRED STOCK, SERIES G
      CONVERTIBLE PREFERRED STOCK, SERIES H CONVERTIBLE PREFERRED STOCK, SERIES
      I CONVERTIBLE PREFERRED STOCK, SERIES J CONVERTIBLE PREFERRED STOCK AND
      SERIES K CONVERTIBLE PREFERRED STOCK.
 
      One hundred thousand (100,000) shares of the authorized and unissued
Preferred Stock of the Corporation are hereby designated "Series A Convertible
Preferred Stock" (the "Series A Preferred Stock"), eighty-two thousand eight
hundred fifty-seven (82,857) shares of the authorized and unissued Preferred
Stock of the Corporation are hereby designated "Series B Convertible Preferred
Stock" (the "Series B Preferred Stock"), nine hundred nineteen thousand two
hundred twenty (919,220) shares of the authorized and unissued Preferred Stock
of the
 
 
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Corporation are hereby designated "Series C Convertible Preferred Stock" (the
"Series C Preferred Stock"), one million five hundred thousand (1,500,000)
shares of the authorized and unissued Preferred Stock of the Corporation are
hereby designated "Series D Convertible Preferred Stock" (the "Series D
Preferred Stock"), one million nine hundred eighty-three thousand three hundred
thirty-four (1,983,334) shares of the authorized and unissued Preferred Stock
are hereby designated "Series E Convertible Preferred Stock" (the "Series E
Preferred Stock"), two million six hundred sixty-six thousand six hundred
sixty-six (2,666,666) shares of the authorized and unissued Preferred Stock are
hereby designated "Series F Convertible Preferred Stock" (the "Series F
Preferred Stock"), three million six hundred sixty-six thousand six hundred
sixty-seven (3,666,667) shares of the authorized and unissued Preferred Stock
are hereby designated "Series G Convertible Preferred Stock" (the "Series G
Preferred Stock"), seven million five hundred seventy-seven thousand three
hundred thirty-four (7,577,334) shares of the authorized and unissued Preferred
Stock are hereby designated "Series H Convertible Preferred Stock" ("the "Series
H Preferred Stock"), five million five hundred seventy-five thousand (5,575,000)
shares of the authorized and unissued Preferred Stock are hereby designated
"Series I Convertible Preferred Stock" (the "Series I Preferred Stock"), three
million seven hundred fifty thousand (3,750,000) shares of the authorized and
unissued Preferred Stock are hereby designated "Series J Convertible Preferred
Stock" (the "Series J Preferred Stock"), and two million five hundred thousand
(2,500,000) shares of the authorized and unissued Preferred Stock are hereby
designated "Series K Convertible Preferred Stock" (the "Series K Preferred
Stock") with the following rights, preferences, powers, privileges and
restrictions, qualifications and limitations.
 
      1.    Dividends.
 
            (a) Cumulative Dividends on Series C Preferred Stock, Series D
Preferred Stock, Series E Preferred Stock, Series F Preferred Stock, Series G
Preferred Stock, Series H Preferred Stock, Series I Preferred Stock, Series J
Preferred Stock and Series K Preferred Stock. (i) The holders of the Series K
Preferred Stock, in preference to the holders of the Common Stock and any other
class of Preferred Stock, shall be entitled to receive, out of funds legally
available therefor, cumulative dividends at a rate of 8% per annum (the
"Dividend Rate") payable if, as and when declared by the Corporation's Board of
Directors or upon the liquidation, dissolution or winding up of the Corporation,
within the meaning of Section 2 hereof, or upon redemption as provided in
Section 6 hereof, and not otherwise, (ii) the holders of the Series J Preferred
Stock, in preference to the holders of the Common Stock and any other class of
Preferred Stock, other than Series K Preferred Stock, shall be entitled to
receive, out of funds legally available therefor, cumulative dividends at the
Dividend Rate payable if, as and when declared by the Corporation's Board of
Directors or upon the liquidation, dissolution or winding up of the Corporation,
within the meaning of Section 2 hereof, or upon redemption as provided in
Section 6 hereof, and not otherwise, (iii) the holders of the Series H Preferred
Stock and Series I Preferred Stock, in preference to the holders of the Common
Stock and any other class of Preferred Stock other than Series J Preferred Stock
and Series K Preferred Stock, shall be entitled to receive, out of funds legally
available therefor, cumulative dividends at the Dividend Rate payable if, as and
when declared by the Corporation's Board of Directors or upon the liquidation,
dissolution or winding up of the Corporation, within the meaning of Section 2
hereof, or upon redemption as provided in Section 6 hereof, and not otherwise
and (iv) the holders of the Series C Preferred Stock, Series D Preferred Stock,
Series E Preferred Stock,
 
 
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Series F Preferred Stock, and Series G Preferred Stock (which, together with the
Series H Preferred Stock, the Series I Preferred Stock, the Series J Preferred
Stock and the Series K Preferred Stock, are collectively referred to as the
"Senior Preferred Stock" ) in preference to the holders of the Common Stock and
any other class of Preferred Stock other than the Series H Preferred Stock, the
Series I Preferred Stock, the Series J Preferred Stock and the Series K
Preferred Stock (collectively, the "Junior Securities") shall be entitled to
receive, out of funds legally available therefor, cumulative dividends at the
Dividend Rate payable if, as and when declared by the Corporation's Board of
Directors or upon the liquidation, dissolution or winding up of the Corporation,
within the meaning of Section 2 hereof, or upon redemption as provided in
Section 6 hereof, and not otherwise. Such dividends on each share of the Senior
Preferred Stock shall be payable in cash and shall accrue at the Dividend Rate
on the sum (such sum being called the "Preference Amount") of the (i) Original
Issue Price (as defined in Section 4(a) below) and (ii) all accumulated and
unpaid dividends accrued thereon from the date of original issuance of such
share, whether or not declared or earned, and whether or not there are profits,
surplus or other funds of the Corporation legally available for the payment of
dividends and shall continue to accrue thereon until the Preference Amount is
paid in full in cash. Upon redemption of the Senior Preferred Stock under
Section 6 hereof, all such accrued and unpaid dividends, whether or not earned
or declared, to and until the date of such redemption shall become immediately
due and payable in full in cash. Upon any conversion of shares of the Senior
Preferred Stock pursuant to Section 5, all rights to such accrued and unpaid
dividends on such shares shall terminate.
 
            (b) No dividend shall be paid or declared, no distribution shall be
made and no redemption shall occur on (i) the Series C Preferred Stock, Series D
Preferred Stock, Series E Preferred Stock, Series F Preferred Stock and Series G
Preferred Stock or on any Junior Securities unless all accrued dividends on the
Series H Preferred Stock, the Series I Preferred Stock, the Series J Preferred
Stock and the Series K Preferred Stock shall have been paid or declared and a
sum sufficient for the payment thereof set apart, and (ii) any Junior Securities
unless all accrued dividends on the Senior Preferred Stock shall have been paid
or declared and a sum sufficient for the payment thereof set apart. Except as
otherwise provided herein, if at any time the Corporation pays less than the
total amount of dividends then accrued with respect to the Senior Preferred
Stock, such payment shall be distributed ratably, first, among the holders of
the Series K Preferred Stock based upon the aggregate accrued but unpaid
dividends on the Series K Preferred Stock held by each such holder, second among
the holders of the Series J Preferred Stock based upon the aggregate accrued but
unpaid dividends on the Series J Preferred Stock held by each such holder,
third, among the holders of the Series H Preferred Stock and Series I Preferred
Stock based upon the aggregate accrued but unpaid dividends on the Series H
Preferred Stock and the Series I Preferred Stock held by each such holder, and
fourth, among the holders of Series C Preferred Stock, Series D Preferred Stock,
Series E Preferred Stock, Series F Preferred Stock and Series G Preferred Stock
based upon the aggregate accrued but unpaid dividends on the Series C Preferred
Stock, Series D Preferred Stock, Series E Preferred Stock, Series F Preferred
Stock and Series G Preferred Stock held by each such holder.
 
            (c) The Corporation shall not declare or pay any dividends or other
distributions on shares of Common Stock until the holders of the Designated
Preferred Stock then outstanding shall have first received, or simultaneously
received, a cash dividend on each outstanding share of Designated Preferred
Stock in an amount at least equal to the product of (x)
 
 
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the per share amount, if any, of the dividends or other distributions to be
declared, paid or set aside for the Common Stock, multiplied by (y) the number
of whole shares of Common Stock into which such Designated Preferred Stock is
then convertible. Any such dividend shall be in addition to the dividends
described in Sections C.1(a) and C.2(a).
 
      2.    Liquidation, Dissolution or Winding Up; Certain Mergers,
            Consolidations and Asset Sales.
 
            (a) In the event of any voluntary or involuntary liquidation,
dissolution or winding up of the Corporation, the holders of shares of the
Series K Preferred Stock shall be paid first out of the assets and legally
available funds of the Corporation available for distribution to its
stockholders, before any payment shall be made to the holders of the
Corporation's capital stock of all classes, an amount per share equal to the
greater of (i) $8.00 per share (in each case subject to appropriate adjustment
in the event of any stock dividend, stock split, combination or other similar
recapitalization affecting such shares), plus all dividends accrued or declared
but unpaid thereon, to and including the date full payment shall be tendered to
the holders of the Series K Preferred Stock or (ii) such amount per share as
would have been payable had each such share been converted into Common Stock
pursuant to Section 4 immediately prior to such liquidation, dissolution or
winding up, plus any dividends declared or accrued but unpaid on such Common
Stock. After payment shall have been made in full to the holders of the Series K
Preferred Stock, the holders of shares of the Series J Preferred Stock shall be
paid second out of the assets and legally available funds of the Corporation
available for distribution to its stockholders, before any payment shall be made
to the holders of the Corporation's capital stock of all classes, an amount per
share equal to the greater of (i) $8.00 per share (in each case subject to
appropriate adjustment in the event of any stock dividend, stock split,
combination or other similar recapitalization affecting such shares), plus all
dividends accrued or declared but unpaid thereon, to and including the date full
payment shall be tendered to the holders of the Series J Preferred Stock, (ii)
if at the time of liquidation, dissolution or winding up of the corporation, the
fair market value of the Common Stock (as reasonably determined by the Board of
Directors or the Compensation Committee thereof) is less than or equal to $4.00
per share, $10.00 per share (in each case subject to appropriate adjustment in
the event of any stock dividend, stock split, combination or other similar
recapitalization affecting such shares), plus all dividends accrued or declared
but unpaid thereon, to and including the date full payment shall be tendered to
the holders of the Series J Preferred Stock, or (iii) such amount per share as
would have been payable had each such share been converted into Common Stock
pursuant to Section 4 immediately prior to such liquidation, dissolution or
winding up, plus any dividends declared or accrued but unpaid on such Common
Stock.
 
            After payment shall have been made in full to the holders of the
Series K Preferred Stock and the Series J Preferred Stock, the holders of shares
of the Series H Preferred Stock and Series I Preferred Stock shall be paid third
out of the assets and legally available funds of the Corporation available for
distribution to its stockholders, before any payment shall be made to the
holders of the Corporation's capital stock of all classes, except for the Series
K Preferred Stock and the Series J Preferred Stock, an amount per share equal to
the greater of (i) (A) $6.38087 per share for the Series H Preferred Stock and
(B) $8.00 per share for the Series I Preferred Stock (in each case subject to
appropriate adjustment in the event of any stock dividend, stock split,
combination or other similar recapitalization affecting such shares), plus all
 
 
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dividends accrued or declared but unpaid thereon, to and including the date full
payment shall be tendered to the holders of the Series H Preferred Stock and the
holders of Series I Preferred Stock, or (ii) such amount per share as would have
been payable had each such share been converted into Common Stock pursuant to
Section 4 immediately prior to such liquidation, dissolution or winding up, plus
any dividends declared or accrued but unpaid on such Common Stock.
 
      No payment shall be made with respect to the Common Stock, Series A
Preferred Stock, Series B Preferred Stock, Series C Preferred Stock, Series D
Preferred Stock, Series E Preferred Stock, Series F Preferred Stock and Series G
Preferred Stock unless and until full payment has been made to the holders of
the Series H Preferred Stock, Series I Preferred Stock, Series J Preferred Stock
and Series K Preferred Stock of the amounts they are entitled to receive under
this Subsection 2(a).
 
      If upon any such liquidation, dissolution or winding up of the Corporation
the remaining assets and surplus funds of the Corporation available for
distribution to its stockholders shall be insufficient to permit the payment in
full to the holders of the Series K Preferred Stock of all amounts distributable
to them under this Subsection 2(a), then the entire assets and surplus funds of
the Corporation available for such distribution shall be distributed ratably
among the holders of the Series K Preferred Stock in proportion to the full
preferential amount each such holder is otherwise entitled to receive under this
Subsection 2(a). If upon any such liquidation, dissolution or winding up of the
Corporation the remaining assets and surplus funds of the Corporation available
for distribution to its stockholders shall be insufficient to permit the payment
in full to the holders of the Series J Preferred Stock of all amounts
distributable to them under this Subsection 2(a), then any remaining assets and
surplus funds available for distribution after the ratable distribution to the
holders of the Series K Preferred Stock shall be distributed ratably among the
holders of the Series J Preferred Stock in proportion to the full preferential
amount each such holder is otherwise entitled to receive under this Subsection
2(a). If upon any such liquidation, dissolution or winding up of the Corporation
the remaining assets and surplus funds of the Corporation available for
distribution to its stockholders shall be insufficient to permit the payment in
full to the holders of the Series H Preferred Stock and Series I Preferred Stock
of all amounts distributable to them under this Subsection 2(a), then any
remaining assets and surplus funds available for distribution after the ratable
distribution to the holders of the Series K Preferred Stock and the Series J
Preferred Stock shall be distributed ratably to the holders of the Series H
Preferred Stock and Series I Preferred Stock in proportion to the full
preferential amount each such holder is otherwise entitled to receive under this
Subsection 2(a).
 
            (b) After such payments shall have been made in full to the holders
of Series H Preferred Stock, Series I Preferred Stock, Series J Preferred Stock
and Series K Preferred Stock, the holders of the Series C Preferred Stock,
Series D Preferred Stock, Series E Preferred Stock, Series F Preferred Stock and
Series G Preferred Stock shall be paid out of the assets and legally available
funds of the Corporation available for distribution to its stockholders, an
amount per share equal to the greater of (i) (A) $1.00 per share for the Series
C Preferred Stock, (B) $1.50 per share for the Series D Preferred Stock, (C)
$3.00 per share for the Series E Preferred Stock, (D) $3.00 per share for the
Series F Preferred Stock, and (E) $3.00 per share for the Series G Preferred
Stock (in each case subject to appropriate adjustment in the event of any stock
dividend, stock split, combination or other similar recapitalization affecting
such shares),
 
 
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<PAGE>
 
plus all dividends accrued or declared but unpaid thereon, to and including the
date full payment shall be tendered to the holders of the Series C Preferred
Stock, Series D Preferred Stock, Series E Preferred Stock, Series F Preferred
Stock and Series G Preferred Stock, or (ii) such amount per share as would have
been payable had each such share of Series C Preferred Stock, Series D Preferred
Stock, Series E Preferred Stock, Series F Preferred Stock and Series G Preferred
Stock been converted into Common Stock pursuant to Section 4 immediately prior
to such liquidation, dissolution or winding up, plus any dividends declared or
accrued but unpaid on such Common Stock.
 
      No payment shall be made with respect to the Common Stock, Series A
Preferred Stock, and Series B Preferred Stock, unless and until full payment has
been made to the holders of the Series C Preferred Stock, Series D Preferred
Stock, Series E Preferred Stock, Series F Preferred Stock, Series G Preferred
Stock, Series H Preferred Stock, Series I Preferred Stock, Series J Preferred
Stock and Series K Preferred Stock of the amounts they are entitled to receive
under Subsections 2(a) and 2(b).
 
      If, after payment in full has been made to the holders of the Series H
Preferred Stock, the holders of Series I Preferred Stock, the holders of Series
J Preferred Stock and the holders of Series K Preferred Stock, the remaining
assets of the Corporation available for distribution to its stockholders shall
be insufficient to pay the holders of shares of the Series C Preferred Stock,
Series D Preferred Stock, Series E Preferred Stock, Series F Preferred Stock and
Series G Preferred Stock the full amounts distributable to them under this
Subsection 2(b), then the entire assets and surplus funds of the Corporation
available for such distribution shall be distributed ratably among the holders
of the Series C Preferred Stock, Series D Preferred Stock, Series E Preferred
Stock, Series F Preferred Stock and Series G Preferred Stock in proportion to
the full preferential amount each such holder is otherwise entitled to receive
under Subsection 2(b).
 
            (c) After the payments described in Subsections 2(a) and 2(b) shall
have been made in full to the holders of the Series C Preferred Stock, Series D
Preferred Stock, Series E Preferred Stock, Series F Preferred Stock, Series G
Preferred Stock, Series H Preferred Stock, Series I Preferred Stock, Series J
Preferred Stock and Series K Preferred Stock, the holders of shares of Series A
Preferred Stock and Series B Preferred Stock shall be shall be paid out of the
assets and legally available funds of the Corporation available for distribution
to its stockholders, an amount per share equal to the greater of (i) (A) $1.00
per share for the Series A Preferred Stock and (B) $1.75 per share for the
Series B Preferred Stock, (in each case subject to appropriate adjustment in the
event of any stock dividend, stock split, combination or other similar
recapitalization affecting such shares), plus all dividends accrued or declared
but unpaid thereon, to and including the date full payment shall be tendered to
the holders of each of the Series A Preferred Stock and Series B Preferred
Stock, or (ii) such amount per share as would have been payable had each such
share of Series A Preferred Stock and Series B Preferred Stock been converted
into Common Stock pursuant to Section 4 immediately prior to such liquidation,
dissolution or winding up, plus all dividends accrued or declared but unpaid on
such Common Stock.
 
      No payment shall be made with respect to the Common Stock unless and until
full payment has been made to the holders of the Series A Preferred Stock,
Series B Preferred Stock, Series C Preferred Stock, Series D Preferred Stock,
Series E Preferred Stock, Series F Preferred
 
 
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<PAGE>
 
Stock, Series G Preferred Stock, Series H Preferred Stock, Series I Preferred
Stock, Series J Preferred Stock and Series K Preferred Stock of the amounts they
are entitled to receive under Subsections 2(a), 2(b) and 2(c).
 
      If, after payment in full has been made to the holders of the Series C
Preferred Stock, Series D Preferred Stock, Series E Preferred Stock, Series F
Preferred Stock, Series G Preferred Stock, Series H Preferred Stock, Series I
Preferred Stock, Series J Preferred Stock and Series K Preferred Stock, the
remaining assets and surplus funds of the Corporation available for distribution
to its stockholders shall be insufficient to permit the payment in full to the
holders of the Series A Preferred Stock and Series B Preferred Stock of all
amounts distributable to them under this Subsection 2(c), then the entire assets
and surplus funds of the Corporation available for such distribution shall be
distributed ratably among the holders of the Series A Preferred Stock and Series
B Preferred Stock in proportion to the full preferential amount each such holder
is otherwise entitled to receive under this Subsection 2(c).
 
            (d) After the payment of all preferential amounts described in
Subsections 2(a), 2(b) and 2(c) shall have been made in full to the holders of
the Designated Preferred Stock and any other class or series of stock of the
Corporation ranking on liquidation on parity with the Designated Preferred
Stock, upon the dissolution, liquidation or winding up of the Corporation, the
holders of shares of Common Stock then outstanding shall be entitled to receive
the remaining assets and surplus funds of the Corporation available for
distribution to its stockholders.
 
            (e) The amounts payable with respect to shares of Series A Preferred
Stock, Series B Preferred Stock, Series C Preferred Stock, Series D Preferred
Stock, Series E Preferred Stock, Series F Preferred Stock, Series G Preferred
Stock, Series H Preferred Stock, Series I Preferred Stock, Series J Preferred
Stock and Series K Preferred Stock under this Subsection 2 are sometimes
hereinafter referred to as the "Series A Liquidation Value," "Series B
Liquidation Value," "Series C Liquidation Value," "Series D Liquidation Value,"
"Series E Liquidation Value," "Series F Liquidation Value," "Series G
Liquidation Value," "Series H Liquidation Value," "Series I Liquidation Value,"
"Series J Liquidation Value," and "Series K Liquidation Value," respectively,
and together are sometimes hereinafter referred to as the "Liquidation Value."
 
            (f) Any consolidation or merger of the Corporation with or into
another corporation or entity, or a sale of all or substantially all of the
assets of the Corporation, shall not be regarded as a liquidation, dissolution
or winding up of the Corporation within the meaning of Section 2; provided,
however, that a consolidation or merger of the Corporation with or into another
corporation or entity as a result of which in excess of 50% of the Corporation's
voting power is transferred, or a sale of all or substantially all of the assets
of the Corporation in which the per share consideration received in such merger,
consolidation or asset sale by the stockholders of the Corporation is less than
or equal to $8.00 (subject to appropriate adjustment in the event of any stock
dividend, stock split, combination or other similar recapitalization affecting
such shares), shall be regarded as a liquidation, dissolution or winding up of
the Corporation within the meaning of Subsection 2(a) with respect to the Series
H Preferred Stock, the Series I Preferred Stock, the Series J Preferred Stock
and the Series K Preferred Stock, in which case, any amounts received by such
holders as a result of such merger or consolidation
 
 
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<PAGE>
 
shall be deemed to be applied toward, and all consideration received by the
Corporation in such asset sale together with all other available assets of the
Corporation shall be distributed toward, the Liquidation Value attributable to
the Series H Preferred Stock, the Series I Preferred Stock, the Series J
Preferred Stock and the Series K Preferred Stock pursuant to Subsection 2(a).
 
      3.    Voting.
 
            (a) Each holder of outstanding shares of Designated Preferred Stock
shall be entitled to the number of votes equal to the number of whole shares of
Common Stock into which the shares of Designated Preferred Stock held by such
holder are then convertible (as adjusted from time to time pursuant to Section 4
hereof), at each meeting of stockholders of the Corporation (and written actions
of stockholders in lieu of meetings) with respect to any and all matters
presented to the stockholders of the Corporation for their action or
consideration. Except as provided by law, by the provisions of Subsection 3(b)
below or by the provisions establishing any other series of Preferred Stock,
holders of Designated Preferred Stock and of any other outstanding series of
Preferred Stock shall vote together with the holders of Common Stock as a single
class.
 
            (b) The Corporation shall not amend, alter or repeal the
preferences, special rights or other powers of the Designated Preferred Stock so
as to affect adversely the Designated Preferred Stock, without the written
consent or affirmative vote of the holders of a majority of the then outstanding
shares of Designated Preferred Stock, given in writing or by vote at a meeting,
consenting or voting (as the case may be) separately as a class. For this
purpose, without limiting the generality of the foregoing, the authorization of
any shares of capital stock with preference or priority over the Designated
Preferred Stock as to the right to receive either dividends or amounts
distributable upon liquidation, dissolution or winding up of the Corporation
shall be deemed to affect adversely the Designated Preferred Stock. However, the
authorization of any shares of capital stock on a parity with the Designated
Preferred Stock as to the right to receive either dividends or amounts
distributable on liquidation, dissolution or winding up of the Corporation shall
not be deemed to affect adversely the Designated Preferred Stock. The number of
authorized shares of Designated Preferred Stock may be increased or decreased
(but not below the number of shares outstanding) by the directors of the
Corporation pursuant to Section 151 of the General Corporation Law of Delaware
or by the affirmative vote of a majority of the then outstanding shares of
Common Stock, Designated Preferred Stock and all other classes of stock of the
Corporation entitled to vote thereon, voting as a single class, irrespective of
the provisions of Section 242(b)(2) of the General Corporation Law of Delaware.
 
            (c) The Corporation shall not (i) authorize any shares of capital
stock on a parity with or senior to any series of Designated Preferred Stock as
to the right to receive either dividends or amounts distributable upon
liquidation, dissolution or winding up of the Corporation or (ii) take any
action involving the merger, consolidation, or reorganization of the Company, or
sale of substantially all of its assets, without the consent or affirmative vote
of the holders of 67% of the then outstanding shares of the Common Stock,
Designated Preferred Stock and all other classes or series of stock of the
Corporation entitled to vote thereon, voting as a single class.
 
 
                                       10
<PAGE>
 
      4. Optional Conversion. The holders of the Designated Preferred Stock
shall have conversion rights as follows (the "Conversion Rights"):
 
            (a) Right to Convert. Each share of Designated Preferred Stock shall
be convertible, at the option of the holder thereof, at any time and from time
to time, and without the payment of additional consideration by the holder
thereof, into such number of fully paid and nonassessable shares of Common Stock
as is determined by dividing the Original Issue Price (as defined below) by the
Conversion Price (as defined below) in effect at the time of conversion. The
"Original Issue Price" shall mean $1.00 for the Series A Preferred Stock, $1.75
for the Series B Preferred Stock, $1.00 for the Series C Preferred Stock, $1.50
for the Series D Preferred Stock, $3.00 for the Series E Preferred Stock, $3.00
for the Series F Preferred Stock, $3.00 for the Series G Preferred Stock,
$6.38087 for the Series H Preferred Stock, $8.00 for the Series I Preferred
Stock, $8.00 for the Series J Preferred Stock and $8.00 for the Series K
Preferred Stock. The "Conversion Price" shall initially be $1.00 for the Series
A Preferred Stock, $1.75 for the Series B Preferred Stock, $1.00 for the Series
C Preferred Stock, $1.50 for the Series D Preferred Stock, $3.00 for the Series
E Preferred Stock, $3.00 for the Series F Preferred Stock, $3.00 for the Series
G Preferred Stock, $6.38087 for the Series H Preferred Stock, $8.00 for the
Series I Preferred Stock, $8.00 for the Series J Preferred Stock and $8.00 for
the Series K Preferred Stock. Such initial Conversion Price, and the rate at
which shares of Designated Preferred Stock may be converted into shares of
Common Stock, shall be subject to adjustment as provided below.
 
      In the event of a liquidation of the Corporation, the Conversion Rights
shall terminate at the close of business on the first full day preceding the
date fixed for the payment of any amounts distributable on liquidation to the
holders of Designated Preferred Stock.
 
            (b) Fractional Shares. No fractional shares of Common Stock shall be
issued upon conversion of the Designated Preferred Stock. In lieu of any
fractional shares to which the holder would otherwise be entitled, the
Corporation shall pay cash equal to such fraction multiplied by the then
effective Conversion Price. All shares of Designated Preferred Stock held by a
holder shall be aggregated in determining whether any fractional shares result
upon conversion of Designated Preferred Stock.
 
            (c) Mechanics of Conversion.
 
                  (i) In order for a holder of Designated Preferred Stock to
convert shares of Designated Preferred Stock into shares of Common Stock, such
holder shall surrender the certificate or certificates for such shares of
Designated Preferred Stock, at the office of the transfer agent for the
Designated Preferred Stock (or at the principal office of the Corporation if the
Corporation serves as its own transfer agent), together with written notice that
such holder elects to convert all or any number of the shares of the Designated
Preferred Stock represented by such certificate or certificates. Such notice
shall state such holders name or the names of the nominees in which such holder
wishes the certificate or certificates for shares of Common Stock to be issued.
If required by the Corporation, certificates surrendered for conversion shall be
endorsed or accompanied by a written instrument or instruments of transfer, in
form satisfactory to the Corporation, duly executed by the registered holder or
his or its attorney duly authorized in writing. The date of receipt of such
certificates and notice by the transfer agent (or by the
 
 
                                       11
<PAGE>
 
Corporation if the Corporation serves as its own transfer agent) shall be the
conversion date ("Conversion Date"). The Corporation shall, as soon as
practicable after the Conversion Date, issue and deliver at such office to such
holder of Designated Preferred Stock, or to his or its nominees, a certificate
or certificates for the number of shares of Common Stock to which such holder
shall be entitled, together with cash in lieu of any fraction of a share. The
holder of Designated Preferred Stock that is converted pursuant to this Section
shall be deemed to be the holder of the number of shares of Common Stock into
which such Designated Preferred Stock is converted as of the Conversion Date for
all purposes, notwithstanding later delivery of the stock certificates
representing such shares of Common Stock.
 
                  (ii) The Corporation shall at all times when the Designated
Preferred Stock shall be outstanding, reserve and keep available out of its
authorized but unissued stock, for the purpose of effecting the conversion of
the Designated Preferred Stock, such number of its duly authorized shares of
Common Stock as shall from time to time be sufficient to effect the conversion
of all outstanding Designated Preferred Stock. Before taking any action which
would cause an adjustment reducing the Conversion Price below the then par value
of the shares of Common Stock issuable upon conversion of the Designated
Preferred Stock, the Corporation will take any corporate action which may, in
the opinion of its counsel, be necessary in order that the Corporation may
validly and legally issue fully paid and nonassessable shares of Common Stock at
such adjusted Conversion Price.
 
                  (iii) Upon any such conversion, no adjustment to the
Conversion Price shall be made for any declared or accrued but unpaid dividends
on the Designated Preferred Stock surrendered for conversion or on the Common
Stock delivered upon conversion.
 
                  (iv) All shares of Designated Preferred Stock which shall have
been surrendered for conversion as herein provided shall no longer be deemed to
be outstanding and all rights with respect to such shares, including the rights,
if any, to receive notices and to vote, shall immediately cease and terminate on
the Conversion Date, except only the right of the holders thereof to receive
shares of Common Stock in exchange therefor and payment of any dividends
declared or accrued but unpaid thereon. Any shares of Designated Preferred Stock
so converted shall be retired and cancelled and shall not be reissued, and the
Corporation (without the need for stockholder action) may from time to time take
such appropriate action as may be necessary to reduce the authorized Designated
Preferred Stock accordingly.
 
                  (v) The Corporation shall pay any and all issue and other
taxes that may be payable in respect of any issuance or delivery of shares of
Common Stock upon conversion of shares of Designated Preferred Stock pursuant to
this Section 4. The Corporation shall not, however, be required to pay any tax
which may be payable in respect of any transfer involved in the issuance and
delivery of shares of Common Stock in a name other than that in which the shares
of Designated Preferred Stock so converted were registered, and no such issuance
or delivery shall be made unless and until the person or entity requesting such
issuance has paid to the Corporation the amount of any such tax or has
established, to the satisfaction of the Corporation, that such tax has been
paid.
 
 
                                       12
<PAGE>
 
            (d) Adjustment for Dilution Price.
 
                  (i) If at any time after the date of the filing of this
Certificate with the Secretary of State of the State of Delaware, the
Corporation shall issue any shares of Common Stock, or shall issue any Common
Stock Equivalents, for a consideration per share less than the Conversion Price
in effect immediately prior to the issuance of such Common Stock or Common Stock
Equivalents for any share of Designated Preferred Stock, the Conversion Price of
such share of Designated Preferred Stock in effect immediately prior to each
such issuance shall be decreased to the amount determined in accordance with the
following formula:
 
            Conversion Price =  P1Q1 + P2Q2
                                -----------
                                  Q1 + Q2
 
      For purposes of the foregoing formula:
 
      P1 = Conversion Price in effect immediately prior to such issuance.
 
      Q1 = Number of shares of Common Stock deemed outstanding (in accordance
           with subparagraph (iii)(F) below) immediately prior to such issuance.
 
      P2 = Average price per share received by the Corporation upon such
           issuance (determined in accordance with subparagraphs (iii)(B) and
           (iii)(C) below).
 
      Q2 = Number of shares of Common Stock issued or sold, or deemed to have
           been issued or sold (in accordance with subparagraph (iii)(C) below)
           upon such issuance.
 
                  (ii) If, after the date of filing of this Certificate with the
Secretary of State of the State of Delaware, and prior to the occurrence of a
Second Triggering Event, as defined in that certain Side Agreement dated on or
about the date hereof, by and between the Corporation and Amgen Inc., a copy of
which will be provided, upon request, to any holder of Series K Preferred Stock
free of charge, the Corporation shall issue any shares of Common Stock, or shall
issue any Common Stock Equivalents, for a consideration per share less than the
Conversion Price for the Series K Preferred Stock in effect immediately prior to
the issuance of such Common Stock or Common Stock Equivalents, then the
Conversion Price for the Series K Preferred Stock in effect immediately prior to
each such issuance shall automatically be decreased to a price equal to the
price paid per share for such Common Stock or Common Stock Equivalents,
provided, that, in no event shall the Conversion Price for the Series K
Preferred Stock be less than $5.50 per share (subject to appropriate adjustment
in the event of any stock dividend, stock split, combination or other similar
recapitalization affecting such shares) as a result of any adjustment pursuant
to this Section 4(d)(ii); provided further, that, if an adjustment to the
Conversion Price of the Series K Preferred Stock is not made pursuant to this
Section 4(d)(ii) due to the foregoing proviso, then the provisions of Section
4(d)(i) will apply to determine the adjustment, if any, to be made to the
Conversion Price of the Series K Preferred Stock as a result of such issuance.
If an adjustment to the Conversion Price of the Series K Preferred Stock is made
pursuant to this Section 4(d)(ii) as a result of an issuance of Common Stock, or
Common Stock Equivalents, then no adjustment will be made to the Conversion
Price of the Series K Preferred Stock pursuant to Section 4(d)(i) as a result of
such issuance.
 
 
                                       13
<PAGE>
 
                  (iii) For purpose of any adjustment of the Conversion Price
pursuant to this Section 4(d), the following provisions shall be applicable:
 
                        (A) "Common Stock Equivalents" means any stock or
security convertible into or exchangeable for Common Stock and any rights,
warrants or options to acquire Common Stock or any such convertible or
exchangeable security.
 
                        (B) The per share consideration for the sale or issuance
of Common Stock shall be the price per share received by the Corporation before
payment of commissions, discounts and other expenses. The value of any non-cash
consideration received or receivable upon the sale or issuance of Common Stock
or Common Stock Equivalents shall be determined in good faith by the Board of
Directors of the Corporation.
 
                        (C) In the case of the sale or issuance of Common Stock
Equivalents, the per share consideration shall be determined by dividing the
maximum number of shares of Common Stock issuable with respect to such Common
Stock Equivalents into the aggregate consideration received by the Corporation
upon the sale or issuance of such Common Stock Equivalents plus the minimum
aggregate amount of any additional consideration receivable by the Corporation
upon the conversion or exercise of such Common Stock Equivalents. Such maximum
number of shares shall be deemed issued on the earlier of the payment date or
record date for a distribution of Common Stock Equivalents.
 
                        (D) If any Common Stock Equivalents included in
adjustments under this Section 4(d) expire or terminate without the Common Stock
to which they related having been issued, the Conversion Price shall be
readjusted to eliminate the effect of the assumed issuance of such Common Stock.
If any Common Stock Equivalents by their terms provide for subsequent increases
in the additional consideration payable for the related Common Stock or for
subsequent decreases in the number of shares of Common Stock obtainable, upon
any such increase or decrease, the Conversion Price shall be appropriately
readjusted to the extent such Common Stock Equivalents have not then expired or
been exercised or converted. The aggregate increase in the Conversion Price
caused by all such readjustments shall not exceed the decrease in the Conversion
Price made upon the issuance of the Common Stock Equivalents to which such
readjustment relates.
 
                        (E) In case the Corporation shall declare a dividend or
make any other distribution upon any stock of the Corporation payable in Common
Stock or Common Stock Equivalents, such Common Stock or Common Stock Equivalents
shall be deemed to have been issued or sold without consideration as of the
earlier of the related record or payment date.
 
                        (F) The number of shares of Common Stock outstanding at
any point in time shall include all shares then issuable or to become issuable
pursuant to any Common Stock Equivalent then issued or to be issued.
 
                        (G) No adjustment to the Conversion Price shall be made
for the following issuances of Common Stock or Common Stock Equivalents: (I) any
dividend or distribution on any Designated Preferred Stock; (II) any stock for
which adjustment of the Conversion Price is made pursuant to subsections 4(e),
4(f), 4(g), or 4(h) below; (III) the
 
 
                                       14
<PAGE>
 
1,410,000 shares of Common Stock issuable upon outstanding warrants; (IV) the
warrants issuable to the holders of the Series J Preferred Stock pursuant to the
Series J Convertible Preferred Stock Purchase Agreement dated as of September
30, 2003, among the Corporation and the Purchasers named therein and the shares
of Common Stock issuable upon exercise thereof; (V) the shares of Common Stock
and/or Series I Stock issuable pursuant to the Stock Purchase Agreement dated as
of September 30, 2003, among the Corporation and the Sellers identified therein;
(VI) up to an aggregate of 5,192,079 shares of Common Stock (or such higher
number as designated by the Corporation's Board of Directors) or options
therefor that are issuable to employees, consultants, or board members of the
Corporation; (VII) the 92,801 shares of Common Stock issuable upon exercise of
outstanding options; (VIII) shares of Common Stock issuable in connection with
any equipment leasing arrangement or technology licensing agreement provided
that such issuances are approved by the Corporation's Board of Directors; (IX)
the shares of Common Stock which are issuable upon conversion of the Designated
Preferred Stock; (X) shares issued in connection with the acquisition by the
Corporation of any other entity or business; and (XI) shares issued pursuant to
a Qualified Public Offering (as defined in subsection 5(a)).
 
                  (e) Adjustment for Stock Splits and Combinations. If the
Corporation shall at any time or from time to time after the filing of this
Certificate with the Secretary of State of the State of Delaware (the "Filing
Date") effect a subdivision of the outstanding Common Stock, the Conversion
Price then in effect immediately before that subdivision shall be
proportionately decreased. If the Corporation shall at any time or from time to
time after the Filing Date effect a subdivision of any of the Designated
Preferred Stock, the Conversion Price with respect to such series of Designated
Preferred Stock then in effect immediately before that subdivision shall be
proportionately increased. If the Corporation shall at any time or from time to
time after the Filing Date combine the outstanding shares of Common Stock, the
Conversion Price then in effect immediately before the combination shall be
proportionately increased. If the Corporation shall at any time or from time to
time after the Filing Date combine the outstanding shares of any Designated
Preferred Stock, the Conversion Price with respect to such series of Designated
Preferred Stock then in effect immediately before the combination shall be
proportionately decreased. Any adjustment under this paragraph shall become
effective at the close of business on the date the subdivision or combination
becomes effective.
 
                  (f) Adjustment for Certain Dividends and Distributions. In the
event the Corporation at any time, or from time to time after the Filing Date
shall make or issue, or fix a record date for the determination of holders of
Common Stock entitled to receive, a dividend or other distribution payable in
additional shares of Common Stock, then and in each such event the Conversion
Price for the Designated Preferred Stock then in effect shall be decreased as of
the time of such issuance or, in the event such a record date shall have been
fixed, as of the close of business on such record date, by multiplying the
Conversion Price then in effect by a fraction:
 
                        (1) the numerator of which shall be the total number of
shares of Common Stock issued and outstanding immediately prior to the time of
such issuance or the close of business on such record date, and
 
                        (2) the denominator of which shall be the total number
of shares of Common Stock issued and outstanding immediately prior to the time
of such issuance
 
 
                                       15
<PAGE>
 
or the close of business on such record date plus the number of shares of Common
Stock issuable in payment of such dividend or distribution; provided, however,
if such record date shall have been fixed and such dividend is not fully paid or
if such distribution is not fully made on the date fixed therefor, the
Conversion Price for the Designated Preferred Stock shall be recomputed
accordingly as of the close of business on such record date and thereafter the
Conversion Price for the Designated Preferred Stock shall be adjusted pursuant
to this paragraph as of the time of actual payment of such dividends or
distributions; and provided further, however, that no such adjustment shall be
made if the holders of Designated Preferred Stock simultaneously receive a
dividend or other distribution of shares of Common Stock in a number equal to
the number of shares of Common Stock as they would have received if all
outstanding shares of Designated Preferred Stock had been converted into Common
Stock on the date of such event.
 
                  (g) Adjustments for Other Dividends and Distributions. In the
event the Corporation at any time or from time to time after the Filing Date
shall make or issue, or fix a record date for the determination of holders of
Common Stock entitled to receive, a dividend or other distribution payable in
securities of the Corporation other than shares of Common Stock, then and in
each such event provision shall be made so that the holders of the Designated
Preferred Stock shall receive upon conversion thereof in addition to the number
of shares of Common Stock receivable thereupon, the amount of securities of the
Corporation that they would have received had the Designated Preferred Stock
been converted into Common Stock on the date of such event and had they
thereafter, during the period from the date of such event to and including the
conversion date, retained such securities receivable by them as aforesaid during
such period, giving application to all adjustments called for during such period
under this paragraph with respect to the rights of the holders of the Designated
Preferred Stock; and provided further, however, that no such adjustment shall be
made if the holders of Designated Preferred Stock simultaneously receive a
dividend or other distribution of such securities in an amount equal to the
amount of such securities as they would have received if all outstanding shares
of Designated Preferred Stock had been converted into Common Stock on the date
of such event.
 
                  (h) Adjustment for Reclassification, Exchange, or
Substitution. If the Common Stock issuable upon the conversion of the Designated
Preferred Stock shall be changed into the same or a different number of shares
of any class or classes of stock, whether by capital reorganization,
reclassification, or otherwise (other than a subdivision or combination of
shares or stock dividend provided for above, or a reorganization, merger,
consolidation, or sale of assets provided for below), then and in each such
event the holder of each such share of Designated Preferred Stock shall have the
right thereafter to convert such share into the kind and amount of shares of
stock and other securities and property receivable upon such reorganization,
reclassification, or other change, by holders of the number of shares of Common
Stock into which such shares of Designated Preferred Stock might have been
converted immediately prior to such reorganization, reclassification, or change,
all subject to further adjustment as provided herein.
 
                  (i) Adjustment for Merger or Reorganization, etc. In case of
any consolidation or merger of the Corporation with or into another corporation
or the sale of all or substantially all of the assets of the Corporation to
another corporation, each share of Designated Preferred Stock shall thereafter
be convertible (or shall be converted into a security which shall
 
 
                                       16
<PAGE>
 
be convertible) into the kind and amount of shares of stock or other securities
or property to which a holder of the number of shares of Common Stock of the
Corporation deliverable upon conversion of such Designated Preferred Stock would
have been entitled upon such consolidation, merger or sale; and, in such case,
appropriate adjustment (as determined in good faith by the Board of Directors)
shall be made in the application of the provisions in this Section 4 set forth
with respect to the rights and interest thereafter of the holders of the
Designated Preferred Stock, to the end that the provisions set forth in this
Section 4 (including provisions with respect to changes in and other adjustments
of the Conversion Price) shall thereafter be applicable, as nearly as reasonably
may be, in relation to any shares of stock or other property thereafter
deliverable upon the conversion of the Designated Preferred Stock.
Notwithstanding the foregoing, no adjustment will be made to the Series H
Preferred Stock, Series I Preferred Stock, Series J Preferred Stock or Series K
Preferred Stock, in the case of any consolidation or merger of the Corporation
with or into another corporation or the sale of all or substantially all of the
assets of the Corporation to another corporation that is treated as a
liquidation under Subsection 2(f) by the holders of the Series H Preferred
Stock, Series I Preferred Stock, Series J Preferred Stock and Series K Preferred
Stock.
 
            (j) No Impairment. The Corporation will not, by amendment of its
Certificate of Incorporation or through any reorganization, transfer of assets,
consolidation, merger, dissolution, issue or sale of securities or any other
voluntary action, avoid or seek to avoid the observance or performance of any of
the terms to be observed or performed hereunder by the Corporation, but will at
all times in good faith assist in the carrying out of all the provisions of this
Section 4 and in the taking of all such action as may be necessary or
appropriate in order to protect the Conversion Rights of the holders of the
Designated Preferred Stock against impairment.
 
            (k) Certificate as to Adjustments. Upon the occurrence of each
adjustment or readjustment of the Conversion Price pursuant to this Section 4,
the Corporation at its expense shall promptly compute such adjustment or
readjustment in accordance with the terms hereof and furnish to each holder of
Designated Preferred Stock a certificate setting forth such adjustment or
readjustment and showing in detail the facts upon which such adjustment or
readjustment is based. The Corporation shall, upon the written request at any
time of any holder of Designated Preferred Stock, furnish or cause to be
furnished to such holder a similar certificate setting forth (i) such
adjustments and readjustments, (ii) the Conversion Price then in effect, and
(iii) the number of shares of Common Stock and the amount, if any, of other
property which then would be received upon the conversion of Designated
Preferred Stock.
 
      5. Mandatory Conversion.
 
            (a) Upon the closing of the sale of shares of the Corporation's
Common Stock, in an underwritten public offering pursuant to an effective
registration statement under the Securities Act of 1933, as amended, resulting
in at least $50,000,000 of gross proceeds to the Corporation and a price per
share of Common Stock of at least $9.70 (appropriately adjusted to reflect the
occurrence of any event described in Section 4) (a "Qualified Public Offering"
and the "Mandatory Conversion Date"), all outstanding shares of Designated
Preferred Stock shall automatically be converted into shares of Common Stock, at
the then effective Conversion Price for such Designated Preferred Stock.
 
 
                                       17
<PAGE>
 
            (b) All holders of record of shares of Designated Preferred Stock
will be given written notice of the Mandatory Conversion Date and the place
designated for mandatory conversion of all such shares of Designated Preferred
Stock pursuant to this Section 5. Such notice shall be sent by first class or
registered mail, postage prepaid, to each record holder of Designated Preferred
Stock at such holder's address last shown on the records of the transfer agent
for the Designated Preferred Stock (or the records of the Corporation, if it
serves as its own transfer agent). Upon receipt of such notice, each holder of
shares of Designated Preferred Stock shall surrender his or its certificate or
certificates for all such shares to the Corporation at the place designated in
such notice, and shall thereafter receive certificates for the number of shares
of Common Stock to which such holder is entitled pursuant to this Section 5. On
the Mandatory Conversion Date, all rights with respect to the Designated
Preferred Stock so converted, including the rights, if any, to receive notices
and vote, will terminate, except only the rights of the holders thereof, upon
surrender of their certificate or certificates therefor, to receive certificates
for the number of shares of Common Stock into which such Designated Preferred
Stock has been converted, and payment of any declared or accrued but unpaid
dividends thereon (all of which shall be deemed to be declared by the Board of
Directors on the Mandatory Conversion Date). If so required by the Corporation,
certificates surrendered for conversion shall be endorsed or accompanied by
written instrument or instruments of transfer, in form satisfactory to the
Corporation, duly executed by the registered holder or by his or its attorney
duly authorized in writing. As soon as practicable after the Mandatory
Conversion Date and the surrender of the certificate or certificates for
Designated Preferred Stock, the Corporation shall cause to be issued and
delivered to such holder, or on his or its written order, a certificate or
certificates for the number of full shares of Common Stock issuable on such
conversion in accordance with the provisions hereof and cash as provided in
Subsection 4(b) in respect of any fraction of a share of Common Stock otherwise
issuable upon such conversion.
 
            (c) All certificates evidencing shares of Designated Preferred Stock
which are required to be surrendered for conversion in accordance with the
provisions hereof shall, from and after the Mandatory Conversion Date, be deemed
to have been retired and cancelled and the shares of Designated Preferred Stock
represented thereby converted into Common Stock for all purposes,
notwithstanding the failure of the holder or holders thereof to surrender such
certificates on or prior to such date. The Corporation may thereafter take such
appropriate action (without the need for stockholder action) as may be necessary
to reduce the authorized Designated Preferred Stock accordingly.
 
      6. Redemption of the Senior Preferred Stock. The shares of Senior
Preferred Stock shall be redeemed as follows:
 
            (a) Optional Redemption. At the written request of the holders of at
least 60% of the then outstanding shares of Senior Preferred Stock, acting as
one class, made at any time on or after November 26, 2007 (the "Trigger Date"),
the Company shall call for redemption, and shall redeem from the holders of the
Senior Preferred Stock not later than ninety (90) days after the Trigger Date
(such date established for redemption, the "Redemption Date") all of the Senior
Preferred Stock at a Redemption Price per share (the "Redemption Price") equal
to the Preference Amount for such series of Senior Preferred Stock. The
Redemption Price for each series of Senior Preferred Stock shall be
appropriately adjusted in the event of any stock
 
 
                                       18
<PAGE>
 
dividend, stock split, combination of shares, reclassification or other similar
event with respect to such series of Senior Preferred Stock.
 
            (b) Redemption Mechanics. Written notice of redemption (the
"Redemption Notice") shall be sent by the Corporation to each holder of record
of shares of Senior Preferred Stock to be redeemed (at the close of business on
the business day next preceding the date on which the Redemption Notice is
given), not less than twenty (20) days nor more than thirty (30) days prior to
the Redemption Date set forth therein, by delivery in person, nationally
recognized courier, mailed by certified or registered mail, return receipt
requested, or sent by telecopier or telex. The Redemption Notice shall be
addressed to each holder at its address as shown by the records of the
Corporation and shall contain the following information:
 
                  (i) the number of shares of the Senior Preferred Stock held by
the holder that are to be redeemed by the Corporation;
 
                  (ii) the Redemption Date and the applicable Redemption Price;
and
 
                  (iii) that the holder is to surrender to the Corporation, at
the place designated therein, its certificate or certificates representing the
shares of the Senior Preferred Stock to be redeemed.
 
      The Corporation, if advised to do so before the close of business on the
Redemption Date by written notice from any holder of record of Senior Preferred
Stock to be redeemed, shall credit against the number of shares of Senior
Preferred Stock required to be redeemed from such holder, and shall not redeem,
the number of shares of Senior Preferred Stock called for redemption which have
been converted by such holder into Common Stock of the Corporation after the
Trigger Date and on or before such Redemption Date.
 
      From and after the close of business on the Redemption Date, unless there
shall have been a default in the payment of the Redemption Price, all rights of
holders of shares of Senior Preferred Stock (except the right to receive the
Redemption Price) shall cease with respect to the shares to be redeemed on the
Redemption Date, and such shares shall not thereafter be transferred on the
books of the Corporation or be deemed to be outstanding for any purpose
whatsoever.
 
            (c) Insufficient Funds for Redemption. If the funds of the
Corporation legally available for redemption of shares of the Senior Preferred
Stock on a Redemption Date are insufficient to redeem the total number of shares
of the Senior Preferred Stock to be redeemed on such Redemption Date, the
holders of the Series H Preferred Stock, Series I Preferred Stock, Series J
Preferred Stock and Series K Preferred Stock in preference to the holders of any
other class of Senior Preferred Stock shall be entitled to redemption of their
shares of Series H Preferred Stock, Series I Preferred Stock, Series J Preferred
Stock and Series K Preferred Stock and thereafter the holders of such other
classes of Senior Preferred Stock shall share ratably in any funds legally
available for redemption of such shares according to the respective amounts
which would be payable to them if the full number of shares to be redeemed on
such Redemption Date were actually redeemed. If the funds of the Corporation
legally available for redemption of shares of the Series H Preferred Stock,
Series I Preferred Stock, Series J Preferred Stock and Series K Preferred Stock
are insufficient to redeem the total number of shares of Series H Preferred
Stock, Series I Preferred Stock, Series J Preferred Stock and
 
 
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Series K Preferred Stock, holders of such shares shall share ratably in any
funds legally available for redemption of such shares according to the
respective amounts which would be payable to them if the full number of shares
to be redeemed on such Redemption Date were actually redeemed. If, for any
reason, the Corporation fails to redeem all shares of the Senior Preferred Stock
entitled to such redemption on the Redemption Date (i) the unredeemed shares
shall remain outstanding and shall continue to have all rights and preferences
provided for herein, (ii) interest shall accrue on the amount owing and unpaid
on the Redemption Date until paid in full at a rate of 12% per annum, or such
higher rate as equals the applicable federal short-term rate and (iii) the
holders of such unredeemed shares shall have the ongoing right to be redeemed
together with such rights and remedies as may be available under applicable law.
At any time thereafter when additional funds of the Corporation are legally
available for the redemption of such shares of the Senior Preferred Stock, such
funds will be used, at the end of the next succeeding fiscal quarter, to redeem
the balance of such shares, or such portion thereof for which funds are then
legally available, on the basis set forth above.
 
            (d) Surrender of Certificates. Each holder of shares of Senior
Preferred Stock to be redeemed under this Section 6 shall surrender the
certificate or certificates representing such shares to the Corporation at the
place designated in the Redemption Notice, and thereupon the Redemption Price
for such shares as set forth in this Section 6(a) shall be paid to the order of
the person whose name appears on such certificate or certificates, and each
surrendered certificate shall be cancelled. In the event that some but not all
of the shares of the Senior Preferred Stock represented by a certificate(s)
surrendered by a holder are being redeemed, the Corporation shall execute and
deliver to such holder a new certificate representing the number of shares of
the Senior Preferred Stock which were not redeemed.
 
            (e) Redeemed or Otherwise Acquired Shares to be Retired. Any shares
of Senior Preferred Stock redeemed pursuant to this Section 6 or otherwise
acquired by the Corporation in any manner whatsoever shall be cancelled and
shall not under any circumstances be reissued. The Corporation may from time to
time take such appropriate corporate action as may be necessary to reduce
accordingly the number of authorized shares of Senior Preferred Stock.
 
      FIFTH: The Corporation is to have perpetual existence.
 
      SIXTH: The Board of Directors of the Corporation is expressly authorized
to exercise all powers granted to the directors by law except insofar as such
powers are limited or denied herein or in the By-laws of the Corporation. In
furtherance of such powers, the Board of Directors of the corporation is
expressly authorized to adopt, amend or repeal the By-laws of the corporation,
but the stockholders may make additional By-laws and may alter or repeal any
By-law whether adopted by them or otherwise.
 
      SEVENTH: Meetings of stockholders may be held within or without the State
of Delaware, as the By-laws provide. The books of the Corporation may be kept
outside the State of Delaware at the main office of the Corporation or such
place or places as may be designated from time to time by the Corporation's
Board of Directors or in the By-laws of the Corporation.
 
 
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Election of Directors need not be by written ballot unless the By-laws of the
Corporation shall so provide.
 
      EIGHTH: A director shall not be personally liable to the Corporation or
its stockholders for monetary damages for breach of fiduciary duty as a
director, except to the extent that the elimination or limitation of liability
is not permitted under the Delaware General Corporation Law as in effect when
such liability is determined. No amendment or repeal of this provision shall
deprive a director of the benefits hereof with respect to any act or omission
occurring prior to such amendment or repeal.
 
      NINTH: The Corporation shall, to the fullest extent permitted by the
General Corporation Law of the State of Delaware, as amended from time to time,
indemnify each person who was or is a party or is threatened to be made a party
to any threatened, pending or completed action, suit or proceeding, whether
civil, criminal, administrative or investigative, by reason of the fact that he
is or was, or has agreed to become, a director or officer of the Corporation, or
is or was serving, or has agreed to serve, at the request of the Corporation, as
a director, officer or trustee of, or in a similar capacity with, another
corporation, partnership, joint venture, trust or other enterprise, against
expenses (including attorneys' fees), judgments, fines and amounts paid in
settlement actually and reasonably incurred by him or on his behalf in
connection with such action, suit or proceeding and any appeal therefrom.
 
      Indemnification may include payment by the Corporation of expenses in
defending an action or proceeding in advance of the final disposition of such
action or proceeding upon receipt of any undertaking by the person indemnified
to repay such payment if it is ultimately determined that such person is not
entitled to indemnification under this Article, which undertaking may be
accepted without reference to the financial ability of such person to make such
repayments.
 
      The Corporation shall not indemnify any such person seeking
indemnification in connection with a proceeding (or part thereof) initiated by
such person unless the initiation thereof was approved by the Board of Directors
of the Corporation.
 
      The indemnification rights provided in this Article (i) shall not be
deemed exclusive of any other rights to which those indemnified may be entitled
under any law, agreement or vote of stockholders or disinterested directors or
otherwise, and (ii) shall inure to the benefit of the heirs, executors and
administrators of such persons. The Corporation may, to the extent authorized
from time to time by its board of directors, grant indemnification rights to
other employees or agents of the Corporation or other persons serving the
Corporation and such rights may be equivalent to, or greater or less than, those
set forth in this Article.
 
      Any person seeking indemnification under this Article shall be deemed to
have met the standard of conduct required for such indemnification unless the
contrary shall be established.
 
      Any amendment or repeal of the provisions of this Article shall not
adversely affect any right or protection of a director or officer of this
Corporation with respect to any act or omission of such director or officer
occurring prior to such amendment or repeal.
 
 
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      TENTH: The Corporation reserves the right to amend, alter, change or
repeal any provision contained in this Certificate of Incorporation, in the
manner now or hereafter prescribed by statute, and all rights conferred upon
stockholders herein are granted subject to this reservation.
 
 
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      IN WITNESS WHEREOF, the Corporation has caused this Certificate to be
signed by its Chief Executive Officer this 23rd day of December, 2003.
 
 
 
 
                                       VIACELL, INC.
 
 
 
 
                                       By: /s/ Marc D. Beer
                                           _____________________________
                                           Marc D. Beer
                                           Chief Executive Officer
 
 
 
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