AMENDED AND RESTATED BY-LAWS
 
                                       OF
 
                              NXSTAGE MEDICAL, INC.
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                                TABLE OF CONTENTS
 
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ARTICLE I
 
STOCKHOLDERS.............................................................     1
   1.1    Place of Meetings..............................................     1
   1.2    Annual Meeting.................................................     1
   1.3    Special Meetings...............................................     1
   1.4    Notice of Meetings.............................................     1
   1.5    Voting List....................................................     1
   1.6    Quorum.........................................................     2
   1.7    Adjournments...................................................     2
   1.8    Voting and Proxies.............................................     2
   1.9    Action at Meeting..............................................     2
   1.10   Nomination of Directors........................................     3
   1.11   Notice of Business at Annual Meetings..........................     5
   1.12   Conduct of Meetings............................................     7
   1.13   No Action by Consent in Lieu of a Meeting......................     8
 
ARTICLE II
 
DIRECTORS................................................................     8
   2.1    General Powers.................................................     8
   2.2    Number, Election and Qualification.............................     8
   2.3    Terms of Office................................................     8
   2.4    Quorum.........................................................     8
   2.5    Action at Meeting..............................................     8
   2.6    Vacancies......................................................     8
   2.7    Resignation....................................................     8
   2.8    Regular Meetings...............................................     9
   2.9    Special Meetings...............................................     9
   2.10   Notice of Special Meetings.....................................     9
   2.11   Meetings by Conference Communications Equipment................     9
   2.12   Action by Consent..............................................     9
   2.13   Committees.....................................................     9
   2.14   Compensation of Directors......................................    10
 
ARTICLE III
 
OFFICERS.................................................................    10
   3.1    Titles.........................................................    10
   3.2    Election.......................................................    10
   3.3    Qualification..................................................    10
   3.4    Tenure.........................................................    10
   3.5    Resignation and Removal........................................    10
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   3.6    Vacancies......................................................    11
   3.7    Chairman of the Board..........................................    11
   3.8    President; Chief Executive Officer.............................    11
   3.9    Vice Presidents................................................    11
   3.10   Secretary and Assistant Secretaries............................    11
   3.11   Treasurer and Assistant Treasurers.............................    12
   3.12   Salaries.......................................................    12
 
ARTICLE IV
 
CAPITAL STOCK............................................................    12
   4.1    Issuance of Stock..............................................    12
   4.2    Certificates of Stock..........................................    12
   4.3    Transfers......................................................    13
   4.4    Lost, Stolen or Destroyed Certificates.........................    13
   4.5    Record Date....................................................    13
 
ARTICLE V
 
GENERAL PROVISIONS.......................................................    14
   5.1    Fiscal Year....................................................    14
   5.2    Corporate Seal.................................................    14
   5.3    Waiver of Notice...............................................    14
   5.4    Voting of Securities...........................................    14
   5.5    Evidence of Authority..........................................    14
   5.6    Certificate of Incorporation...................................    14
   5.7    Severability...................................................    14
   5.8    Pronouns.......................................................    15
 
ARTICLE VI
 
AMENDMENTS...............................................................    15
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                                    ARTICLE I
 
                                  STOCKHOLDERS
 
     1.1 Place of Meetings. All meetings of stockholders shall be held at such
place as may be designated from time to time by the Board of Directors, the
Chairman of the Board, the Chief Executive Officer or the President or, if not
so designated, at the principal office of the corporation.
 
     1.2 Annual Meeting. The annual meeting of stockholders for the election of
directors and for the transaction of such other business as may properly be
brought before the meeting shall be held on a date and at a time designated by
the Board of Directors, the Chairman of the Board, the Chief Executive Officer
or the President (which date shall not be a legal holiday in the place where the
meeting is to be held). If no annual meeting is held in accordance with the
foregoing provisions, a special meeting may be held in lieu of the annual
meeting, and any action taken at that special meeting shall have the same effect
as if it had been taken at the annual meeting, and in such case all references
in these By-laws to the annual meeting of the stockholders shall be deemed to
refer to such special meeting.
 
     1.3 Special Meetings. Special meetings of stockholders for any purpose or
purposes may be called at any time by the Board of Directors, the Chairman of
the Board, the Chief Executive Officer or the President, but such special
meetings may not be called by any other person or persons. Business transacted
at any special meeting of stockholders shall be limited to matters relating to
the purpose or purposes stated in the notice of meeting.
 
     1.4 Notice of Meetings. Except as otherwise provided by law, notice of each
meeting of stockholders, whether annual or special, shall be given not less than
10 nor more than 60 days before the date of the meeting to each stockholder
entitled to vote at such meeting. Without limiting the manner by which notice
otherwise may be given to stockholders, any notice shall be effective if given
by a form of electronic transmission consented to (in a manner consistent with
the General Corporation Law of the State of Delaware) by the stockholder to whom
the notice is given. The notices of all meetings shall state the place, date and
time of the meeting and the means of remote communications, if any, by which
stockholders and proxyholders may be deemed to be present in person and vote at
such meeting. The notice of a special meeting shall state, in addition, the
purpose or purposes for which the meeting is called. If notice is given by mail,
such notice shall be deemed given when deposited in the United States mail,
postage prepaid, directed to the stockholder at such stockholder's address as it
appears on the records of the corporation. If notice is given by electronic
transmission, such notice shall be deemed given at the time specified in Section
232 of the General Corporation Law of the State of Delaware.
 
     1.5 Voting List. The Secretary shall prepare, at least 10 days before every
meeting of stockholders, a complete list of the stockholders entitled to vote at
the meeting, arranged in alphabetical order, and showing the address of each
stockholder and the number of shares registered in the name of each stockholder.
Such list shall be open to the examination of any stockholder, for any purpose
germane to the meeting, for a period of at least 10 days prior to the meeting:
(a) on a reasonably accessible electronic network, provided that the information
required to gain access to such list is provided with notice of the meeting, or
(b) during ordinary
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business hours, at the principal place of business of the corporation. The list
shall also be produced and kept at the time and place of the meeting during the
whole time thereof, and may be inspected by any stockholder who is present.
 
     1.6 Quorum. Except as otherwise provided by law, the Certificate of
Incorporation or these By-laws, the holders of a majority in voting power of the
shares of the capital stock of the corporation issued and outstanding and
entitled to vote at the meeting, present in person, present by means of remote
communication in a manner, if any, authorized by the Board of Directors in its
sole discretion, or represented by proxy, shall constitute a quorum for the
transaction of business. A quorum, once established at a meeting, shall not be
broken by the withdrawal of enough votes to leave less than a quorum.
 
     1.7 Adjournments. Any meeting of stockholders may be adjourned from time to
time to any other time and to any other place at which a meeting of stockholders
may be held under these By-laws by the stockholders present or represented at
the meeting and entitled to vote, although less than a quorum, or, if no
stockholder is present, by any officer entitled to preside at or to act as
secretary of such meeting. It shall not be necessary to notify any stockholder
of any adjournment of less than 30 days if the time and place of the adjourned
meeting, and the means of remote communication, if any, by which stockholders
and proxyholders may be deemed to be present in person and vote at such
adjourned meeting, are announced at the meeting at which adjournment is taken,
unless after the adjournment a new record date is fixed for the adjourned
meeting. At the adjourned meeting, the corporation may transact any business
which might have been transacted at the original meeting.
 
     1.8 Voting and Proxies. Each stockholder shall have one vote for each share
of stock entitled to vote held of record by such stockholder and a proportionate
vote for each fractional share so held, unless otherwise provided by law or the
Certificate of Incorporation. Each stockholder of record entitled to vote at a
meeting of stockholders may vote in person (including by means of remote
communications, if any, by which stockholders may be deemed to be present in
person and vote at such meeting) or may authorize another person or persons to
vote for such stockholder by a proxy executed or transmitted in a manner
permitted by the General Corporation Law of the State of Delaware by the
stockholder or such stockholder's authorized agent and delivered (including by
electronic transmission) to the Secretary of the corporation. No such proxy
shall be voted upon after three years from the date of its execution, unless the
proxy expressly provides for a longer period.
 
     1.9 Action at Meeting. When a quorum is present at any meeting, any matter
other than the election of directors to be voted upon by the stockholders at
such meeting shall be decided by the affirmative vote of the holders of a
majority in voting power of the shares of stock present or represented and
voting on such matter (or if there are two or more classes of stock entitled to
vote as separate classes, then in the case of each such class, the holders of a
majority in voting power of the shares of stock of that class present or
represented and voting on such matter), except when a different vote is required
by law, the Certificate of Incorporation or these By-laws. When a quorum is
present at any meeting, any election by stockholders of directors shall be
determined by a plurality of the votes cast by the stockholders entitled to vote
on the election.
 
 
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     1.10 Nomination of Directors.
 
          (a) Except for (1) any directors entitled to be elected by the holders
of preferred stock, (2) any directors elected in accordance with Section 2.9
hereof by the Board of Directors to fill a vacancy or newly-created
directorships or (3) as otherwise required by applicable law or stock market
regulation, only persons who are nominated in accordance with the procedures in
this Section 1.10 shall be eligible for election as directors. Nomination for
election to the Board of Directors at a meeting of stockholders may be made (i)
by or at the direction of the Board of Directors or (ii) by any stockholder of
the corporation who (x) complies with the notice procedures set forth in Section
1.10(b) and (y) is a stockholder of record on the date of the giving of such
notice and on the record date for the determination of stockholders entitled to
vote at such meeting.
 
          (b) To be timely, a stockholder's notice must be received in writing
by the Secretary at the principal executive offices of the corporation as
follows: (i) in the case of an election of directors at an annual meeting of
stockholders, not less than 90 days nor more than 120 days prior to the first
anniversary of the preceding year's annual meeting; provided, however, that (x)
in the case of the annual meeting of stockholders of the corporation to be held
in 2006 or (y) in the event that the date of the annual meeting in any other
year is advanced by more than 20 days, or delayed by more than 60 days, from the
first anniversary of the preceding year's annual meeting, a stockholder's notice
must be so received not earlier than the 120th day prior to such annual meeting
and not later than the close of business on the later of (A) the 90th day prior
to such annual meeting and (B) the tenth day following the day on which notice
of the date of such annual meeting was mailed or public disclosure of the date
of such annual meeting was made, whichever first occurs; or (ii) in the case of
an election of directors at a special meeting of stockholders, provided that the
Board of Directors has determined that directors shall be elected at such
meeting, not earlier than the 120th day prior to such special meeting and not
later than the close of business on the later of (x) the 90th day prior to such
special meeting and (y) the tenth day following the day on which notice of the
date of such special meeting was mailed or public disclosure of the date of such
special meeting was made, whichever first occurs. In no event shall the
adjournment or postponement of an annual meeting (or the public announcement
thereof) commence a new time period (or extend any time period) for the giving
of a stockholder's notice.
 
     The stockholder's notice to the Secretary shall set forth: (A) as to each
proposed nominee (1) such person's name, age, business address and, if known,
residence address, (2) such person's principal occupation or employment, (3) the
class and number of shares of stock of the corporation which are beneficially
owned by such person, and (4) any other information concerning such person that
must be disclosed as to nominees in proxy solicitations pursuant to Regulation
14A under the Securities Exchange Act of 1934, as amended (the "Exchange Act");
(B) as to the stockholder giving the notice (1) such stockholder's name and
address, as they appear on the corporation's books, (2) the class and number of
shares of stock of the corporation which are owned, beneficially and of record,
by such stockholder, (3) a description of all arrangements or understandings
between such stockholder and each proposed nominee and any other person or
persons (including their names) pursuant to which the nomination(s) are to be
made by such stockholder, (4) a representation that such stockholder intends to
appear in person
 
 
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or by proxy at the meeting to nominate the person(s) named in its notice and (5)
a representation whether the stockholder intends or is part of a group which
intends (x) to deliver a proxy statement and/or form of proxy to holders of at
least the percentage of the corporation's outstanding capital stock required to
elect the nominee and/or (y) otherwise to solicit proxies from stockholders in
support of such nomination; and (C) as to the beneficial owner, if any, on whose
behalf the nomination is being made (1) such beneficial owner's name and
address, (2) the class and number of shares of stock of the corporation which
are beneficially owned by such beneficial owner, (3) a description of all
arrangements or understandings between such beneficial owner and each proposed
nominee and any other person or persons (including their names) pursuant to
which the nomination(s) are to be made and (4) a representation whether the
beneficial owner intends or is part of a group which intends (x) to deliver a
proxy statement and/or form of proxy to holders of at least the percentage of
the corporation's outstanding capital stock requirement to elect the nominee
and/or (y) otherwise to solicit proxies from stockholders in support of such
nomination. In addition, to be effective, the stockholder's notice must be
accompanied by the written consent of the proposed nominee to serve as a
director if elected. The corporation may require any proposed nominee to furnish
such other information as may reasonably be required to determine the
eligibility of such proposed nominee to serve as a director of the corporation.
A stockholder shall not have complied with this Section 1.10(b) if the
stockholder (or beneficial owner, if any, on whose behalf the nomination is
made) solicits or does not solicit, as the case may be, proxies in support of
such stockholder's nominee in contravention of the representations with respect
thereto required by this Section 1.10.
 
          (c) The chairman of any meeting shall have the power and duty to
determine whether a nomination was made in accordance with the provisions of
this Section 1.10 (including whether the stockholder or beneficial owner, if
any, on whose behalf the nomination is made solicited (or is part of a group
which solicited) or did not so solicit, as the case may be, proxies in support
of such stockholder's nominee in compliance with the representations with
respect thereto required by this Section 1.10), and if the chairman should
determine that a nomination was not made in accordance with the provisions of
this Section 1.10, the chairman shall so declare to the meeting and such
nomination shall be disregarded.
 
          (d) Except as otherwise required by law, nothing in this Section 1.10
shall obligate the corporation or the Board of Directors to include in any proxy
statement or other stockholder communication distributed on behalf of the
corporation or the Board of Directors information with respect to any nominee
for director submitted by a stockholder.
 
          (e) Notwithstanding the foregoing provisions of this Section 1.10, if
the stockholder (or a qualified representative of the stockholder) does not
appear at the annual or special meeting of stockholders of the corporation to
present a nomination, such nomination shall be disregarded, notwithstanding that
proxies in respect of such vote may have been received by the corporation. For
purposes of this Section 1.10, to be considered a qualified representative of
the stockholder, a person must be authorized by a written instrument executed by
such stockholder or an electronic transmission delivered by such stockholder to
act for such stockholder as proxy at the meeting of stockholders and such person
must produce such written instrument or electronic transmission, or a reliable
reproduction of the written instrument or electronic transmission, at the
meeting of stockholders.
 
 
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          (f) For purposes of this Section 1.10, "public disclosure" shall
include disclosure in a press release reported by the Dow Jones New Service,
Associated Press or comparable national news service or in a document publicly
filed by the corporation with the Securities and Exchange Commission pursuant to
Section 13, 14 or 15(d) of the Exchange Act.
 
     1.11 Notice of Business at Annual Meetings.
 
          (a) At any annual meeting of the stockholders, only such business
shall be conducted as shall have been properly brought before the meeting. To be
properly brought before an annual meeting, business must be (1) specified in the
notice of meeting (or any supplement thereto) given by or at the direction of
the Board of Directors, (2) otherwise properly brought before the meeting by or
at the direction of the Board of Directors, or (3) properly brought before the
meeting by a stockholder. For business to be properly brought before an annual
meeting by a stockholder, (i) if such business relates to the nomination of a
person for election as a director of the corporation, the procedures in Section
1.10 must be complied with and (ii) if such business relates to any other
matter, the business must constitute a proper matter under Delaware law for
stockholder action and the stockholder must (x) have given timely notice thereof
in writing to the Secretary in accordance with the procedures set forth in
Section 1.11(b) and (y) be a stockholder of record on the date of the giving of
such notice and on the record date for the determination of stockholders
entitled to vote at such annual meeting.
 
          (b) To be timely, a stockholder's notice must be received in writing
by the Secretary at the principal executive offices of the corporation not less
than 90 days nor more than 120 days prior to the first anniversary of the
preceding year's annual meeting; provided, however, that (x) in the case of the
annual meeting of stockholders of the corporation to be held in 2006 or (y) in
the event that the date of the annual meeting [in any other year is advanced by
more than 20 days, or delayed by more than 60 days, from the first anniversary
of the preceding year's annual meeting, a stockholder's notice must be so
received not earlier than the 120th day prior to such annual meeting and not
later than the close of business on the later of (A) the 90th day prior to such
annual meeting and (B) the tenth day following the day on which notice of the
date of such annual meeting was mailed or public disclosure of the date of such
annual meeting was made, whichever first occurs. In no event shall the
adjournment or postponement of an annual meeting (or the public announcement
thereof) commence a new time period (or extend any time period) for the giving
of a stockholder's notice.
 
     The stockholder's notice to the Secretary shall set forth as to each matter
the stockholder proposes to bring before the annual meeting (1) a brief
description of the business desired to be brought before the annual meeting, the
text relating to the business (including the text of any resolutions proposed
for consideration and in the event that such business includes a proposal to
amend the By-laws, the language of the proposed amendment), and the reasons for
conducting such business at the annual meeting, (2) the name and address, as
they appear on the corporation's books, of the stockholder proposing such
business, and the name and address of the beneficial owner, if any, on whose
behalf the proposal is made, (3) the class and number of shares of stock of the
corporation which are owned, of record and beneficially, by the stockholder and
beneficial owner, if any, (4) a description of all arrangements or
understandings between such stockholder or such beneficial owner, if any, and
any other person or persons
 
 
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(including their names) in connection with the proposal of such business by such
stockholder and any material interest of the stockholder or such beneficial
owner, if any, in such business, (5) a representation that such stockholder
intends to appear in person or by proxy at the annual meeting to bring such
business before the meeting and (6) a representation whether the stockholder or
the beneficial owner, if any, intends or is part of a group which intends (x) to
deliver a proxy statement and/or form of proxy to holders of at least the
percentage of the corporation's outstanding capital stock required to approve or
adopt the proposal and/or (y) otherwise to solicit proxies from stockholders in
support of such proposal. Notwithstanding anything in these By-laws to the
contrary, no business shall be conducted at any annual meeting of stockholders
except in accordance with the procedures set forth in this Section 1.11;
provided that any stockholder proposal which complies with Rule 14a-8 of the
proxy rules (or any successor provision) promulgated under the Securities
Exchange Act of 1934, as amended, and is to be included in the corporation's
proxy statement for an annual meeting of stockholders shall be deemed to comply
with the requirements of this Section 1.11. A stockholder shall not have
complied with this Section 1.11(b) if the stockholder (or beneficial owner, if
any, on whose behalf the nomination is made) solicits or does not solicit, as
the case may be, proxies in support of such stockholder's proposal in
contravention of the representations with respect thereto required by this
Section 1.11.
 
          (c) The chairman of any meeting shall have the power and duty to
determine whether business was properly brought before the meeting in accordance
with the provisions of this Section 1.11 (including whether the stockholder or
beneficial owner, if any, on whose behalf the proposal is made solicited (or is
part of a group which solicited) or did not so solicit, as the case may be,
proxies in support of such stockholder's proposal in compliance with the
representation with respect thereto required by this Section 1.11), and if the
chairman should determine that business was not properly brought before the
meeting in accordance with the provisions of this Section 1.11, the chairman
shall so declare to the meeting and such business shall not be brought before
the meeting.
 
          (d) Notwithstanding the foregoing provisions of this Section 1.11, if
the stockholder (or a qualified representative of the stockholder) does not
appear at the annual meeting of stockholders of the corporation to present
business, such business shall not be considered, notwithstanding that proxies in
respect of such vote may have been received by the corporation. For purposes of
this Section 1.11, to be considered a qualified representative of the
stockholder, a person must be authorized by a written instrument executed by the
such stockholder or an electronic transmission delivered by such stockholder to
act for such stockholder as a proxy at the meeting of stockholders and such
person must produce such written instrument or electronic transmission, or a
reliable reproduction of the written instrument or electronic transmission, at
the meeting of stockholders.
 
          (e) For purposes of this Section 1.11, "public disclosure" shall
include disclosure in a press release reported by the Dow Jones New Service,
Associated Press or comparable national news service or in a document publicly
filed by the corporation with the Securities and Exchange Commission pursuant to
Section 13, 14 or 15(d) of the Exchange Act.
 
 
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     1.12 Conduct of Meetings.
 
          (a) Meetings of stockholders shall be presided over by the Chairman of
the Board, if any, or in the Chairman's absence by the Vice Chairman of the
Board, if any, or in the Vice Chairman's absence by the Chief Executive Officer,
or in the Chief Executive Officer's absence, by the President, or in the
President's absence by a Vice President, or in the absence of all of the
foregoing persons by a chairman designated by the Board of Directors, or in the
absence of such designation by a chairman chosen by vote of the stockholders at
the meeting. The Secretary shall act as secretary of the meeting, but in the
Secretary's absence the chairman of the meeting may appoint any person to act as
secretary of the meeting.
 
          (b) The Board of Directors may adopt by resolution such rules,
regulations and procedures for the conduct of any meeting of stockholders of the
corporation as it shall deem appropriate including, without limitation, such
guidelines and procedures as it may deem appropriate regarding the participation
by means of remote communication of stockholders and proxyholders not physically
present at a meeting. Except to the extent inconsistent with such rules,
regulations and procedures as adopted by the Board of Directors, the chairman of
any meeting of stockholders shall have the right and authority to prescribe such
rules, regulations and procedures and to do all such acts as, in the judgment of
such chairman, are appropriate for the proper conduct of the meeting. Such
rules, regulations or procedures, whether adopted by the Board of Directors or
prescribed by the chairman of the meeting, may include, without limitation, the
following: (i) the establishment of an agenda or order of business for the
meeting; (ii) rules and procedures for maintaining order at the meeting and the
safety of those present; (iii) limitations on attendance at or participation in
the meeting to stockholders of record of the corporation, their duly authorized
and constituted proxies or such other persons as shall be determined; (iv)
restrictions on entry to the meeting after the time fixed for the commencement
thereof; and (v) limitations on the time allotted to questions or comments by
participants. Unless and to the extent determined by the Board of Directors or
the chairman of the meeting, meetings of stockholders shall not be required to
be held in accordance with the rules of parliamentary procedure.
 
          (c) The chairman of the meeting shall announce at the meeting when the
polls for each matter to be voted upon at the meeting will be opened and closed.
If no announcement is made, the polls shall be deemed to have opened when the
meeting is convened and closed upon the final adjournment of the meeting. After
the polls close, no ballots, proxies or votes or any revocations or changes
thereto may be accepted.
 
          (d) In advance of any meeting of stockholders, the Board of Directors,
the Chairman of the Board, the Chief Executive Officer or the President shall
appoint one or more inspectors of election to act at the meeting and make a
written report thereof. One or more other persons may be designated as alternate
inspectors to replace any inspector who fails to act. If no inspector or
alternate is present, ready and willing to act at a meeting of stockholders, the
chairman of the meeting shall appoint one or more inspectors to act at the
meeting. Unless otherwise required by law, inspectors may be officers, employees
or agents of the corporation. Each inspector, before entering upon the discharge
of such inspector's duties, shall take and sign an oath faithfully to execute
the duties of inspector with strict impartiality and according to the
 
 
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best of such inspector's ability. The inspector shall have the duties prescribed
by law and shall take charge of the polls and, when the vote in completed, shall
make a certificate of the result of the vote taken and of such other facts as
may be required by law.
 
     1.13 No Action by Consent in Lieu of a Meeting. Stockholders of the
corporation may not take any action by written consent in lieu of a meeting.
 
                                   ARTICLE II
 
                                    DIRECTORS
 
     2.1 General Powers. The business and affairs of the corporation shall be
managed by or under the direction of a Board of Directors, who may exercise all
of the powers of the corporation except as otherwise provided by law or the
Certificate of Incorporation.
 
     2.2 Number, Election and Qualification. Subject to the rights of holders of
any series of Preferred Stock to elect directors, the number of directors of the
Corporation shall be established by the Board of Directors. Election of
directors need not be by written ballot. Directors need not be stockholders of
the corporation.
 
     2.3 Terms of Office. Each director shall serve for a term ending on the
date of the annual meeting following the annual meeting at which such director
was elected; provided, that the term of each director shall continue until the
election and qualification of a successor, or until such director's earlier
death, resignation or removal.
 
     2.4 Quorum. The greater of (a) a majority of the directors at any time in
office and (b) one-third of the number of directors fixed by the Board of
Directors shall constitute a quorum. If at any meeting of the Board of Directors
there shall be less than such a quorum, a majority of the directors present may
adjourn the meeting from time to time without further notice other than
announcement at the meeting, until a quorum shall be present.
 
     2.5 Action at Meeting. Every act or decision done or made by a majority of
the directors present at a meeting duly held at which a quorum is present shall
be regarded as the act of the Board of Directors unless a greater number is
required by law or by the Certificate of Incorporation.
 
     2.6 Vacancies. Subject to the rights of holder of any series of Preferred
Stock, any vacancy or newly-created directorships on the Board of Directors,
however occurring, shall be filled only by vote of a majority of the directors
then in office, although less than a quorum, or by a sole remaining director and
shall not be filled by the stockholders. A director elected to fill a vacancy
shall hold office until the next election of the class for which such director
shall have been chosen, subject to the election and qualification of a successor
or until such director's earlier death, resignation or removal.
 
     2.7 Resignation. Any director may resign by delivering a resignation in
writing or by electronic transmission to the corporation at its principal office
or to the Chairman of the Board, the Chief Executive Officer, the President or
the Secretary. Such resignation shall be effective
 
 
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upon receipt unless it is specified to be effective at some later time or upon
the happening of some later event.
 
     2.8 Regular Meetings. Regular meetings of the Board of Directors may be
held without notice at such time and place as shall be determined from time to
time by the Board of Directors; provided that any director who is absent when
such a determination is made shall be given notice of the determination. A
regular meeting of the Board of Directors may be held without notice immediately
after and at the same place as the annual meeting of stockholders.
 
     2.9 Special Meetings. Special meetings of the Board of Directors may be
held at any time and place designated in a call by the Chairman of the Board,
the Chief Executive Officer, the President, two or more directors, or by one
director in the event that there is only a single director in office.
 
     2.10 Notice of Special Meetings. Notice of any special meeting of directors
shall be given to each director by the Secretary or by the officer or one of the
directors calling the meeting. Notice shall be duly given to each director (a)
in person or by telephone at least 24 hours in advance of the meeting, (b) by
sending written notice via reputable overnight courier, telecopy or electronic
mail, or delivering written notice by hand, to such director's last known
business, home or electronic mail address at least 48 hours in advance of the
meeting, or (c) by sending written notice via first-class mail to such
director's last known business or home address at least 72 hours in advance of
the meeting. A notice or waiver of notice of a meeting of the Board of Directors
need not specify the purposes of the meeting.
 
     2.11 Meetings by Conference Communications Equipment. Directors may
participate in meetings of the Board of Directors or any committee thereof by
means of conference telephone or other communications equipment by means of
which all persons participating in the meeting can hear each other, and
participation by such means shall constitute presence in person at such meeting.
 
     2.12 Action by Consent. Any action required or permitted to be taken at any
meeting of the Board of Directors or of any committee thereof may be taken
without a meeting, if all members of the Board of Directors or committee, as the
case may be, consent to the action in writing or by electronic transmission, and
the written consents or electronic transmissions are filed with the minutes of
proceedings of the Board of Directors or committee.
 
     2.13 Committees. The Board of Directors may designate one or more
committees, each committee to consist of one or more of the directors of the
corporation. The Board of Directors may designate one or more directors as
alternate members of any committee, who may replace any absent or disqualified
member at any meeting of the committee. In the absence or disqualification of a
member of a committee, the member or members of the committee present at any
meeting and not disqualified from voting, whether or not such member or members
constitute a quorum, may unanimously appoint another member of the Board of
Directors to act at the meeting in the place of any such absent or disqualified
member. Any such committee, to the extent provided in the resolution of the
Board of Directors and subject to the provisions of law, shall have and may
exercise all the powers and authority of the Board of Directors in the
management of the business and affairs of the corporation and may authorize the
seal of the
 
 
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corporation to be affixed to all papers which may require it. Each such
committee shall keep minutes and make such reports as the Board of Directors may
from time to time request. Except as the Board of Directors may otherwise
determine, any committee may make rules for the conduct of its business, but
unless otherwise provided by the directors or in such rules, its business shall
be conducted as nearly as possible in the same manner as is provided in these
By-laws for the Board of Directors. Except as otherwise provided in the
Certificate of Incorporation, these Bylaws, or the resolution of the Board of
Directors designating the committee, a committee may create one or more
subcommittees, each subcommittee to consist of one or more members of the
committee, and delegate to a subcommittee any or all of the powers and authority
of the committee.
 
     2.14 Compensation of Directors. Directors may be paid such compensation for
their services and such reimbursement for expenses of attendance at meetings as
the Board of Directors may from time to time determine. No such payment shall
preclude any director from serving the corporation or any of its parent or
subsidiary entities in any other capacity and receiving compensation for such
service.
 
                                  ARTICLE III
 
                                    OFFICERS
 
     3.1 Titles. The officers of the corporation shall consist of a Chief
Executive Officer, a President, a Secretary, a Treasurer and such other officers
with such other titles as the Board of Directors shall determine, including a
Chairman of the Board, a Vice Chairman of the Board, and one or more Vice
Presidents, Assistant Treasurers, and Assistant Secretaries. The Board of
Directors may appoint such other officers as it may deem appropriate.
 
     3.2 Election. The Chief Executive Officer, President, Treasurer and
Secretary shall be elected annually by the Board of Directors at its first
meeting following the annual meeting of stockholders. Other officers may be
appointed by the Board of Directors at such meeting or at any other meeting.
 
     3.3 Qualification. No officer need be a stockholder. Any two or more
offices may be held by the same person.
 
     3.4 Tenure. Except as otherwise provided by law, by the Certificate of
Incorporation or by these By-laws, each officer shall hold office until such
officer's successor is elected and qualified, unless a different term is
specified in the resolution electing or appointing such officer, or until such
officer's earlier death, resignation or removal.
 
     3.5 Resignation and Removal. Any officer may resign by delivering a written
resignation to the corporation at its principal office or to the Chief Executive
Officer, the President or the Secretary. Such resignation shall be effective
upon receipt unless it is specified to be effective at some later time or upon
the happening of some later event.
 
Any officer may be removed at any time, with or without cause, by vote of a
majority of the directors then in office.
 
 
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Except as the Board of Directors may otherwise determine, no officer who resigns
or is removed shall have any right to any compensation as an officer for any
period following such officer's resignation or removal, or any right to damages
on account of such removal, whether such officer's compensation be by the month
or by the year or otherwise, unless such compensation is expressly provided for
in a duly authorized written agreement with the corporation.
 
     3.6 Vacancies. The Board of Directors may fill any vacancy occurring in any
office for any reason and may, in its discretion, leave unfilled for such period
as it may determine any offices other than those of Chief Executive Officer,
President, Treasurer and Secretary. Each such successor shall hold office for
the unexpired term of such officer's predecessor and until a successor is
elected and qualified, or until such officer's earlier death, resignation or
removal.
 
     3.7 Chairman of the Board. The Board of Directors may appoint from its
members a Chairman of the Board, who need not be an employee or officer of the
corporation. If the Board of Directors appoints a Chairman of the Board, such
Chairman shall perform such duties and possess such powers as are assigned by
the Board of Directors and, if the Chairman of the Board is also designated as
the corporation's Chief Executive Officer, shall have the powers and duties of
the Chief Executive Officer prescribed in Section 3.8 of these By-laws. Unless
otherwise provided by the Board of Directors, the Chairman of the Board shall
preside at all meetings of the Board of Directors and stockholders.
 
     3.8 President; Chief Executive Officer. Unless the Board of Directors has
designated the Chairman of the Board or another person as the corporation's
Chief Executive Officer, the President shall be the Chief Executive Officer of
the corporation. The Chief Executive Officer shall have general charge and
supervision of the business of the Corporation subject to the direction of the
Board of Directors. The President shall perform such other duties and shall have
such other powers as the Board of Directors or the Chief Executive Officer (if
the President is not the Chief Executive Officer) may from time to time
prescribe. In the event of the absence, inability or refusal to act of the Chief
Executive Officer or the President (if the President is not the Chief Executive
Officer), the Vice President (or if there shall be more than one, the Vice
Presidents in the order determined by the Board of Directors) shall perform the
duties of the Chief Executive Officer and when so performing such duties shall
have all the powers of and be subject to all the restrictions upon the Chief
Executive Officer.
 
     3.9 Vice Presidents. Any Vice President shall perform such duties and
possess such powers as the Board of Directors or the Chief Executive Officer may
from time to time prescribe. The Board of Directors may assign to any Vice
President the title of Executive Vice President, Senior Vice President or any
other title selected by the Board of Directors.
 
     3.10 Secretary and Assistant Secretaries. The Secretary shall perform such
duties and shall have such powers as the Board of Directors or the Chief
Executive Officer may from time to time prescribe. In addition, the Secretary
shall perform such duties and have such powers as are incident to the office of
the secretary, including without limitation the duty and power to give notices
of all meetings of stockholders and special meetings of the Board of Directors,
to attend all meetings of stockholders and the Board of Directors and keep a
record of the proceedings, to maintain a stock ledger and prepare lists of
stockholders and their addresses as required, to be
 
 
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custodian of corporate records and the corporate seal and to affix and attest to
the same on documents.
 
     Any Assistant Secretary shall perform such duties and possess such powers
as the Board of Directors, the Chief Executive Officer or the Secretary may from
time to time prescribe. In the event of the absence, inability or refusal to act
of the Secretary, the Assistant Secretary (or if there shall be more than one,
the Assistant Secretaries in the order determined by the Board of Directors)
shall perform the duties and exercise the powers of the Secretary.
 
     In the absence of the Secretary or any Assistant Secretary at any meeting
of stockholders or directors, the chairman of the meeting shall designate a
temporary secretary to keep a record of the meeting.
 
     3.11 Treasurer and Assistant Treasurers. The Treasurer shall perform such
duties and shall have such powers as may from time to time be assigned by the
Board of Directors or the Chief Executive Officer. In addition, the Treasurer
shall perform such duties and have such powers as are incident to the office of
treasurer, including without limitation the duty and power to keep and be
responsible for all funds and securities of the corporation, to deposit funds of
the corporation in depositories selected in accordance with these By-laws, to
disburse such funds as ordered by the Board of Directors, to make proper
accounts of such funds, and to render as required by the Board of Directors
statements of all such transactions and of the financial condition of the
corporation.
 
     The Assistant Treasurers shall perform such duties and possess such powers
as the Board of Directors, the Chief Executive Officer or the Treasurer may from
time to time prescribe. In the event of the absence, inability or refusal to act
of the Treasurer, the Assistant Treasurer (or if there shall be more than one,
the Assistant Treasurers in the order determined by the Board of Directors)
shall perform the duties and exercise the powers of the Treasurer.
 
     3.12 Salaries. Officers of the corporation shall be entitled to such
salaries, compensation or reimbursement as shall be fixed or allowed from time
to time by the Board of Directors.
 
                                   ARTICLE IV
 
                                  CAPITAL STOCK
 
     4.1 Issuance of Stock. Subject to the provisions of the Certificate of
Incorporation, the whole or any part of any unissued balance of the authorized
capital stock of the corporation or the whole or any part of any shares of the
authorized capital stock of the corporation held in the corporation's treasury
may be issued, sold, transferred or otherwise disposed of by vote of the Board
of Directors in such manner, for such lawful consideration and on such terms as
the Board of Directors may determine.
 
     4.2 Certificates of Stock. Every holder of stock of the corporation shall
be entitled to have a certificate, in such form as may be prescribed by law and
by the Board of Directors, certifying the number and class of shares owned by
such holder in the corporation. Each such
 
 
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certificate shall be signed by, or in the name of the corporation by, the
Chairman or Vice Chairman, if any, of the Board of Directors, or the President
or a Vice President, and the Treasurer or an Assistant Treasurer, or the
Secretary or an Assistant Secretary of the corporation. Any or all of the
signatures on the certificate may be a facsimile.
 
     Each certificate for shares of stock which are subject to any restriction
on transfer pursuant to the Certificate of Incorporation, these By-laws,
applicable securities laws or any agreement among any number of stockholders or
among such holders and the corporation shall have conspicuously noted on the
face or back of the certificate either the full text of the restriction or a
statement of the existence of such restriction.
 
     There shall be set forth on the face or back of each certificate
representing shares of such class or series of stock of the corporation a
statement that the corporation will furnish without charge to each stockholder
who so requests a copy of the full text of the powers, designations, preferences
and relative, participating, optional or other special rights of each class of
stock or series thereof and the qualifications, limitations or restrictions of
such preferences and/or rights.
 
     4.3 Transfers. Except as otherwise established by rules and regulations
adopted by the Board of Directors, and subject to applicable law, shares of
stock may be transferred on the books of the corporation by the surrender to the
corporation or its transfer agent of the certificate representing such shares
properly endorsed or accompanied by a written assignment or power of attorney
properly executed, and with such proof of authority or the authenticity of
signature as the corporation or its transfer agent may reasonably require.
Except as may be otherwise required by law, by the Certificate of Incorporation
or by these By-laws, the corporation shall be entitled to treat the record
holder of stock as shown on its books as the owner of such stock for all
purposes, including the payment of dividends and the right to vote with respect
to such stock, regardless of any transfer, pledge or other disposition of such
stock until the shares have been transferred on the books of the corporation in
accordance with the requirements of these By-laws.
 
     4.4 Lost, Stolen or Destroyed Certificates. The corporation may issue a new
certificate of stock in place of any previously issued certificate alleged to
have been lost, stolen or destroyed, upon such terms and conditions as the Board
of Directors may prescribe, including the presentation of reasonable evidence of
such loss, theft or destruction and the giving of such indemnity and posting of
such bond as the Board of Directors may require for the protection of the
corporation or any transfer agent or registrar.
 
     4.5 Record Date. The Board of Directors may fix in advance a date as a
record date for the determination of the stockholders entitled to notice of or
to vote at any meeting of stockholders, or entitled to receive payment of any
dividend or other distribution or allotment of any rights in respect of any
change, conversion or exchange of stock, or for the purpose of any other lawful
action. Such record date shall not be more than 60 nor less than 10 days before
the date of such meeting, nor more than 60 days prior to any other action to
which such record date relates.
 
     If no record date is fixed, the record date for determining stockholders
entitled to notice of or to vote at a meeting of stockholders shall be at the
close of business on the day before the
 
 
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<PAGE>
day on which notice is given, or, if notice is waived, at the close of business
on the day before the day on which the meeting is held. If no record date is
fixed, the record date for determining stockholders for any other purpose shall
be at the close of business on the day on which the Board of Directors adopts
the resolution relating to such purpose.
 
     A determination of stockholders of record entitled to notice of or to vote
at a meeting of stockholders shall apply to any adjournment of the meeting;
provided, however, that the Board of Directors may fix a new record date for the
adjourned meeting.
 
                                   ARTICLE V
 
                               GENERAL PROVISIONS
 
     5.1 Fiscal Year. Except as from time to time otherwise designated by the
Board of Directors, the fiscal year of the corporation shall begin on the first
day of January of each year and end on the last day of December in each year.
 
     5.2 Corporate Seal. The corporate seal shall be in such form as shall be
approved by the Board of Directors.
 
     5.3 Waiver of Notice. Whenever notice is required to be given by law, by
the Certificate of Incorporation or by these By-laws, a written waiver signed by
the person entitled to notice, or a waiver by electronic transmission by the
person entitled to notice, whether before, at or after the time stated in such
notice, shall be deemed equivalent to notice. Attendance of a person at a
meeting shall constitute a waiver of notice of such meeting, except when the
person attends a meeting for the express purpose of objecting at the beginning
of the meeting, to the transaction of any business because the meeting is not
lawfully called or convened.
 
     5.4 Voting of Securities. Except as the Board of Directors may otherwise
designate, the Chief Executive Officer, the President or the Treasurer may waive
notice of, and act as, or appoint any person or persons to act as, proxy or
attorney-in-fact for this corporation (with or without power of substitution) at
any meeting of stockholders or securityholders of any other entity, the
securities of which may be held by this corporation.
 
     5.5 Evidence of Authority. A certificate by the Secretary, or an Assistant
Secretary, or a temporary Secretary, as to any action taken by the stockholders,
directors, a committee or any officer or representative of the corporation shall
as to all persons who rely on the certificate in good faith be conclusive
evidence of such action.
 
     5.6 Certificate of Incorporation. All references in these By-laws to the
Certificate of Incorporation shall be deemed to refer to the Certificate of
Incorporation of the corporation, as amended and in effect from time to time.
 
     5.7 Severability. Any determination that any provision of these By-laws is
for any reason inapplicable, illegal or ineffective shall not affect or
invalidate any other provision of these By-laws.
 
 
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     5.8 Pronouns. All pronouns used in these By-laws shall be deemed to refer
to the masculine, feminine or neuter, singular or plural, as the identity of the
person or persons may require.
 
                                   ARTICLE VI
 
                                   AMENDMENTS
 
     These By-laws may be altered, amended or repealed, in whole or in part, or
new By-laws may be adopted by the Board of Directors or by the stockholders as
provided in the Certificate of Incorporation.
 
 
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