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                                                                    Exhibit 10.3

                               ACTIVBIOTICS, INC.

                                 THIRD AMENDMENT
                                       TO
                           2001 EQUITY INCENTIVE PLAN

     This THIRD AMENDMENT (this "Amendment") to the 2001 Equity Incentive Plan
(the "Plan") of ActivBiotics, Inc., a Delaware corporation (the "Company"), is
being adopted at a meeting of the Board of Directors of the Company on April 27,
2005, and by the written consent of the stockholders of the Company dated as of
June ___, 2005 (the "Effective Date"). Effective from and after the Effective
Date, the Plan is hereby amended as follows:

     1. Section 4 of the Plan hereby is amended by replacing the number
"11,000,000" in the fourth (4th) line thereof with the number "15,139,062", said
amendment being for the purpose of increasing the total number of shares of
common stock, $0.01 par value per share, that may be subject to options granted
under the Plan from 11,000,000 shares to 15,139,062 shares.

     2. Except to the extent amended hereby, all of the terms, provisions and
conditions set forth in the Plan are hereby ratified and confirmed and shall
remain in full force and effect. The Plan and this Amendment, along with all
prior amendments to the Plan, shall be read and construed together as a single
instrument.

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                               ACTIVBIOTICS, INC.

                                SECOND AMENDMENT
                                       TO
                           2001 EQUITY INCENTIVE PLAN

     This SECOND AMENDMENT (this "Amendment") to the 2001 Equity Incentive Plan
(the "Plan") of ActivBiotics, Inc., a Delaware corporation (the "Company"), is
being adopted at a meeting of the Board of Directors of the Company on January
22, 2004, and by the written consent of the stockholders of the Company dated as
of January 22, 2004 (the "Effective Date"). Effective from and alter the
Effective Date, the Plan is hereby amended as follows:

     1. Section 4 of the Plan hereby is amended by replacing the number
"8,500,000" in the fourth (4th) line thereof with the number "11,000,000", said
amendment being for the purpose of increasing the total number of shares of
common stock, $0.01 par value per share, that may be subject to options granted
under the Plan from 8,500,000 shares to 11,000,000 shares.

     2. Except to the extent amended hereby, all of the terms, provisions and
conditions set forth in the Plan are hereby ratified and confirmed and shall
remain in full force and effect. The Plan and this Amendment, along with all
prior amendments to the Plan, shall be read and construed together as a single
instrument.

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                               ACTIVBIOTICS, INC.

                                 FIRST AMENDMENT
                                       TO
                           2001 EQUITY INCENTIVE PLAN

     This FIRST AMENDMENT (this "Amendment") to the 2001 Equity Incentive Plan
(the "Plan") of ActivBiotics, Inc., a Delaware corporation (the "Company"), is
being adopted by the written consent of the Board of Directors of the Company
dated as of April 30, 2003, and by the written consent of the stockholders of
the Company dated as of April 30, 2003 (the "Effective Date"). Effective from
and after the Effective Date, the Plan is hereby amended as follows:

     1. Section 4 of the Plan hereby is amended by replacing the number
"5,500,000" in the fourth (4th) line thereof with the number "8,500,000", said
amendment being for the purpose of increasing the total number of shares of
common stock, $0.01 par value per share, that may be subject to options granted
under the Plan from 5,500,000 shares to 8,500,000 shares.

     2. Except to the extent amended hereby, all of the terms, provisions and
conditions set forth in the Plan are hereby ratified and confirmed and shall
remain in full force and effect. The Plan and this Amendment, along with all
prior amendments to the Plan, shall be read and construed together as a single
instrument.

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                               ACTIVBIOTICS, INC.
                        (f/k/a Merlin Technologies, Inc.)

                           2001 EQUITY INCENTIVE PLAN

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                                TABLE OF CONTENTS

1.    Purpose                                                                  1
2     Definitions                                                              1
3.    Term of the Plan                                                         3
4.    Stock Subject to the Plan                                                3
5.    Administration                                                           3
6.    Authorization and Eligibility                                            4
7.    Specific Terms of Awards                                                 5
8.    Adjustment Provisions                                                    9
9.    Settlement of Awards                                                    10
10.   Reservation of Stock                                                    13
11.   No Special Employment or Other Rights                                   13
12.   Nonexclusivity of the Plan                                              13
13.   Termination and Amendment of the Plan                                   13
14.   Notices and Other Communications                                        14
15.   Governing Law                                                           14

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                               ACTIVBIOTICS, INC.
                        (f/k/a Merlin Technologies, Inc.)

                           2001 EQUITY INCENTIVE PLAN

     1. PURPOSE. This Plan is intended to encourage ownership of Common Stock by
employees, consultants and directors of ActivBiotics, Inc. (f/k/a Merlin
Technologies, Inc.) (the "Company") and its Affiliates and to provide additional
incentive for them to promote the success of the Company's business. The Plan is
intended to be an incentive stock option plan within the meaning of Section 422
of the Code, but not all Awards are required to be Incentive Options.

     2. DEFINITIONS. As used in this Plan, the following terms shall have the
following meanings:

     2.1. ACCELERATE, ACCELERATED, and ACCELERATION, when used with respect to
an Option, means that as of the time of reference the Option will become
exercisable with respect to some or all of the shares of Common Stock for which
it was not then otherwise exercisable by its terms, and, when used with respect
to Restricted Stock, means that the Risk of Forfeiture otherwise applicable to
the Stock shall expire with respect to some or all of the shares of Restricted
Stock then still otherwise subject to the Risk of Forfeiture.

     2.2. ACQUISITION means a merger or consolidation of the Company with or
into another person or the sale, transfer, or other disposition of all or
substantially all of the Company's assets to one or more other persons in a
single transaction or series of related transactions, unless securities
possessing more than 50% of the total combined voting power of the survivor's or
acquirer's outstanding securities (or the securities of any parent thereof) are
held by a person or persons who held securities possessing more than 50% of the
total combined voting power of the Company immediately prior to that
transaction.

     2.3. AFFILIATE means any corporation, partnership, limited liability
company, business trust, or other entity controlling, controlled by or under
common control with the Company.

     2.4. AWARD means any grant or sale pursuant to the Plan of Options,
Restricted Stock or Stock Grants.

     2.5. AWARD AGREEMENT means an agreement between the Company and the
recipient of an Award, setting forth the terms and conditions of the Award.

     2.6. BOARD means the Company's Board of Directors.

     2.7. CHANGE OF CONTROL means any of the following transactions:

          (a) any Acquisition, or

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                                        2


          (b) any person or group of persons (within the meaning of Section
13(d)(3) of the Securities Exchange Act of 1934, as amended and in effect from
time to time), other than the Company or an Affiliate, directly or indirectly
acquires beneficial ownership (determined pursuant to Securities and Exchange
Commission Rule 13d-3 promulgated under the said Exchange Act) of securities
possessing more than 50% of the total combined voting power of the Company's
outstanding securities pursuant to a tender or exchange offer made directly to
the Company's stockholders.

     2.8. CODE means the Internal Revenue Code of 1986, as amended from time to
time, or any successor statute thereto, and any regulations issued from time to
time thereunder.

     2.9. COMMITTEE means any committee of the Board delegated responsibility by
the Board for the administration of the Plan, as provided in Section 5 of the
Plan. For any period during which no such committee is in existence "Committee"
shall mean the Board and all authority and responsibility assigned to the
Committee under the Plan shall be exercised, if at all, by the Board.

     2.10. COMMON STOCK or STOCK means common stock, par value $0.01 per share,
of the Company.

     2.11. COMPANY means ActivBiotics, Inc. (f/k/a Merlin Technologies, Inc.), a
corporation organized under the laws of the State of Delaware.

     2.12. GRANT DATE means the date as of which an Option is granted, as
determined under Section 7.1(a).

     2.13. INCENTIVE OPTION means an Option which by its terms is to be treated
as an "incentive stock option" within the meaning of Section 422 of the Code.

     2.14. MARKET VALUE means the value of a share of Common Stock on any date
as determined by the Committee.

     2.15. NONSTATUTORY OPTION means any Option that is not an Incentive Option.

     2.16. OPTION means an option to purchase shares of Common Stock.

     2.17. OPTIONEE means a Participant to whom an Option shall have been
granted under the Plan.

     2.18. PARTICIPANT means any holder of an outstanding Award under the Plan.

     2.19. PLAN means this 2001 Equity Incentive Plan of the Company, as amended
from time to time, and including any attachments or addenda hereto.

     2.20. RESTRICTED STOCK means a grant or sale of shares of Common Stock to a
Participant subject to a Risk of Forfeiture.

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     2.21. RESTRICTION PERIOD means the period of time, established by the
Committee in connection with an Award of Restricted Stock, during which the
shares of Restricted Stock are subject to a Risk of Forfeiture described in the
applicable Award Agreement.

     2.22. RISK OF FORFEITURE means a limitation on the right of the Participant
to retain Restricted Stock, including a right in the Company to reacquire the
Shares at less than their then Market Value, arising because of the occurrence
or non-occurrence of specified events or conditions.

     2.23. STOCK GRANT means the grant of shares of Common Stock not subject to
restrictions or other forfeiture conditions.

     2.24. STOCKHOLDERS' AGREEMENT means any agreement by and among the holders
of at least a majority of the outstanding voting securities of the Company and
setting forth, among other provisions, restrictions upon the transfer of shares
of Stock or on the exercise of rights appurtenant thereto (including but not
limited to voting rights).

     2.25. TEN PERCENT OWNER means a person who owns, or is deemed within the
meaning of Section 422(b)(6) of the Code to own, stock possessing more than 10%
of the total combined voting power of all classes of stock of the Company (or
any Affiliate). Whether a person is a Ten Percent Owner shall be determined with
respect to an Option based on the facts existing immediately prior to the Grant
Date of the Option.

     3. TERM OF THE PLAN. Unless the Plan shall have been earlier terminated by
the Board, Awards may be granted under this Plan at any time in the period
commencing on the date of approval of the Plan by the Board and ending
immediately prior to the tenth anniversary of the earlier of the adoption of the
Plan by the Board or approval of the Plan by the Company's stockholders. Awards
granted pursuant to the Plan within that period shall not expire solely by
reason of the termination of the Plan. Awards of Incentive Options granted prior
to stockholder approval of the Plan are expressly conditioned upon such
approval, but in the event of the failure of the stockholders to approve the
Plan shall thereafter and for all purposes be deemed to constitute Nonstatutory
Options.

     4. STOCK SUBJECT TO THE PLAN. At no time shall the number of shares of
Common Stock issued pursuant to or subject to outstanding Awards granted under
the Plan exceed 5,500,000 shares of Common Stock; SUBJECT, HOWEVER, to the
provisions of Section 8 of the Plan. For purposes of applying the foregoing
limitation, if any Option expires, terminates, or is cancelled for any reason
without having been exercised in full, or if any Award of Restricted Stock is
forfeited by the recipient, the shares not purchased by the Optionee or
forfeited by the recipient shall again be available for Awards to be granted
under the Plan. Shares of Common Stock issued pursuant to the Plan may be either
authorized but unissued shares or shares held by the Company in its treasury.

     5. ADMINISTRATION. The Plan shall be administered by the Committee;
PROVIDED, HOWEVER, that at any time and on any one or more occasions the Board
may itself exercise any of the powers and responsibilities assigned the
Committee under the

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                                        4


Plan and when so acting shall have the benefit of all of the provisions of the
Plan pertaining to the Committee's exercise of its authorities hereunder; and
PROVIDED FURTHER, HOWEVER, that the Committee may delegate to a director or
executive officer or officers the authority to grant Awards hereunder to
employees who are not officers, and to consultants, in accordance with such
guidelines as the Committee shall set forth at any time or from time to time.
Subject to the provisions of the Plan, the Committee shall have complete
authority, in its discretion, to make or to select the manner of making all
determinations with respect to each Award to be granted by the Company under the
Plan including the employee, consultant or director to receive the Award and the
form of Award. In making such determinations, the Committee may take into
account the nature of the services rendered by the respective employees,
consultants, and directors, their present and potential contributions to the
success of the Company and its Affiliates, and such other factors as the
Committee in its discretion shall deem relevant. Subject to the provisions of
the Plan, the Committee shall also have complete authority to interpret the
Plan, to prescribe, amend and rescind rules and regulations relating to it, to
determine the terms and provisions of the respective Award Agreements (which
need not be identical), and to make all other determinations necessary or
advisable for the administration of the Plan. The Committee's determinations
made in good faith on matters referred to in the Plan shall be final, binding
and conclusive on all persons having or claiming any interest under the Plan or
an Award made pursuant to hereto.

     6. AUTHORIZATION AND ELIGIBILITY. The Committee may grant from time to time
and at any time prior to the termination of the Plan one or more Awards, either
alone or in combination with any other Awards, to any employee of or consultant
to one or more of the Company and its Affiliates or to non-employee member of
the Board or of any board of directors (or similar governing authority) of any
Affiliate. However, only employees of the Company, and of any parent or
subsidiary corporations of the Company, as defined in Sections 424(e) and (f),
respectively, of the Code, shall be eligible for the grant of an Incentive
Option. Further, in no event shall the number of shares of Common Stock covered
by Options or other Awards granted to any one person in any one calendar year
exceed 25% of the aggregate number of shares of Common Stock subject to the
Plan.

     Each grant of an Award shall be subject to all applicable terms and
conditions of the Plan (including but not limited to any specific terms and
conditions applicable to that type of Award set out in the following Section),
and such other terms and conditions, not inconsistent with the terms of the
Plan, as the Committee may prescribe. No prospective Participant shall have any
rights with respect to an Award, unless and until such Participant has executed
an agreement evidencing the Award, delivered a fully executed copy thereof to
the Company, and otherwise complied with the applicable terms and conditions of
such Award.

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                                        5


     7. SPECIFIC TERMS OF AWARDS

     7.1. OPTIONS.

          (a) DATE OF GRANT. The granting of an Option shall take place at the
time specified in the Award Agreement. Only if expressly so provided in the
applicable Award Agreement shall the Grant Date be the date on which the Award
Agreement shall have been duly executed and delivered by the Company and the
Optionee.

          (b) EXERCISE PRICE. The price at which shares of Common Stock may be
acquired under each Incentive Option shall be not less than 100% of the Market
Value of Common Stock on the Grant Date, or not less than 110% of the Market
Value of Common Stock on the Grant Date if the Optionee is a Ten Percent Owner.
The price at which shares may be acquired under each Nonstatutory Option shall
not be so limited solely by reason of this Section.

          (c) OPTION PERIOD. No Incentive Option may be exercised on or after
the tenth anniversary of the Grant Date, or on or after the fifth anniversary of
the Grant Date if the Optionee is a Ten Percent Owner. The Option period under
each Nonstatutory Option shall not be so limited solely by reason of this
Section.

          (d) EXERCISABILITY. An Option may be immediately exercisable or become
exercisable in such installments, cumulative or non-cumulative, as the Committee
may determine. In the case of an Option not otherwise immediately exercisable in
full, the Committee may Accelerate such Option in whole or in part at any time;
PROVIDED, HOWEVER, that in the case of an Incentive Option, any such
Acceleration of the Option would not cause the Option to fail to comply with the
provisions of Section 422 of the Code or the Optionee consents to the
Acceleration.

          (e) TERMINATION OF ASSOCIATION WITH THE COMPANY. Unless the Committee
shall provide otherwise with respect to any Option, if the Optionee's employment
or other association with the Company and its Affiliates ends for any reason,
including because of the Optionee's employer ceasing to be an Affiliate, any
outstanding Option of the Optionee shall cease to be exercisable in any respect
not later than 90 days following that event and, for the period it remains
exercisable following that event, shall be exercisable only to the extent
exercisable at the date of that event. Military or sick leave or other bona fide
leave shall not be deemed a termination of employment or other association,
PROVIDED that it does not exceed the longer of ninety (90) days or the period
during which the absent Optionee's reemployment rights, if any, are guaranteed
by statute or by contract.

          (f) TRANSFERABILITY. Except as otherwise provided in this subsection
(f), Options shall not be transferable, and no Option or interest therein may be
sold, transferred, pledged, assigned, or otherwise alienated or hypothecated,
other than by will or by the laws of descent and distribution. All of a
Participant's rights in any Option may be exercised during the life of the
Participant only by the Participant or the Participant's legal representative.
However, the Committee may, at or after the grant of a

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                                        6


Nonstatutory Option, provide that such Option may be transferred by the
recipient to a family member; PROVIDED, HOWEVER, that any such transfer is
without payment of any consideration whatsoever and that no transfer of an
Option shall be valid unless first approved by the Committee, acting in its sole
discretion. For this purpose, "family member" means any child, stepchild,
grandchild, parent, stepparent, spouse, former spouse, sibling, niece, nephew,
mother-in-law, father-in-law, son-in-law, daughter-in-law, brother-in-law, or
sister-in-law, including adoptive relationships, any person sharing the
employee's household (other than a tenant or employee), a trust in which the
foregoing persons have more than fifty percent (50%) of the beneficial
interests, a foundation in which the foregoing persons (or the Participant)
control the management of assets, and any other entity in which these persons
(or the Participant) own more than fifty percent (50%) of the voting interests.

          (g) METHOD OF EXERCISE. An Option may be exercised by the Optionee
giving written notice, in the manner provided in Section 14, specifying the
number of shares with respect to which the Option is then being exercised. The
notice shall be accompanied by payment in the form of cash or check payable to
the order of the Company in an amount equal to the exercise price of the shares
to be purchased or, if the Committee had so authorized on the grant of an
Incentive Option or on or after grant of an Nonstatutory Option (and subject to
such conditions, if any, as the Committee may deem necessary to avoid adverse
accounting effects to the Company) by delivery to the Company of:

               (i) shares of Common Stock having a Market Value equal to the
     exercise price of the shares to be purchased, or

               (ii) the Optionee's executed promissory note in the principal
     amount equal to the exercise price of the shares to be purchased and
     otherwise in such form as the Committee shall have approved.

If the Stock is then currently traded on an established market, payment of any
exercise price may also be made through and under the terms and conditions of
any formal cashless exercise program authorized by the Company entailing the
sale of the Stock subject to an Option in a brokered transaction (other than to
the Company). Receipt by the Company of such notice and payment in any
authorized or combination of authorized means shall constitute the exercise of
the Option. Within thirty (30) days thereafter but subject to the remaining
provisions of the Plan, the Company shall deliver or cause to be delivered to
the Optionee or his agent a certificate or certificates for the number of shares
then being purchased. Such shares shall be fully paid and nonassessable.

          (h) LIMIT ON INCENTIVE OPTION CHARACTERIZATION. An Incentive Option
shall be considered to be an Incentive Option only to the extent that the number
of shares of Common Stock for which the Option first becomes exercisable in a
calendar year do not have an aggregate Market Value (as of the date of the grant
of the Option) in excess of the "current limit". The current limit for any
Optionee for any calendar year shall be $100,000 MINUS the aggregate Market
Value at the date of grant of the number of shares

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of Common Stock available for purchase for the first time in the same year under
each other Incentive Option previously granted to the Optionee under the Plan,
and under each other incentive stock option previously granted to the Optionee
under any other incentive stock option plan of the Company and its Affiliates,
after December 31, 1986. Any shares of Common Stock which would cause the
foregoing limit to be violated shall be deemed to have been granted under a
separate Nonstatutory Option, otherwise identical in its terms to those of the
Incentive Option.

          (i) NOTIFICATION OF DISPOSITION. Each person exercising any Incentive
Option granted under the Plan shall be deemed to have covenanted with the
Company to report to the Company any disposition of such shares prior to the
expiration of the holding periods specified by Section 422(a)(1) of the Code
and, if and to the extent that the realization of income in such a disposition
imposes upon the Company federal, state, local or other withholding tax
requirements, or any such withholding is required to secure for the Company an
otherwise available tax deduction, to remit to the Company an amount in cash
sufficient to satisfy those requirements.

          (j) RIGHTS PENDING EXERCISE. No person holding an Option shall be
deemed for any purpose to be a stockholder of the Company with respect to any of
the shares of Stock issuable pursuant to his Option, except to the extent that
the Option shall have been exercised with respect thereto and, in addition, a
certificate shall have been issued therefor and delivered to such holder or his
agent.

     7.2. RESTRICTED STOCK.

          (a) PURCHASE PRICE. Shares of Restricted Stock shall be issued under
the Plan for such consideration, in cash, other property or services, or any
combination thereof, as is determined by the Committee.

          (b) ISSUANCE OF CERTIFICATES. Each Participant receiving a Restricted
Stock Award, subject to subsection (c) below, shall be issued a stock
certificate in respect of such shares of Restricted Stock. Such certificate
shall be registered in the name of such Participant, and, if applicable, shall
bear an appropriate legend referring to the terms, conditions, and restrictions
applicable to such Award substantially in the following form:

     The transferability of this certificate and the shares represented by this
     certificate are subject to the terms and conditions of the ActivBiotics,
     Inc. 2001 Equity Incentive Plan and an Award Agreement entered into by the
     registered owner and ActivBiotics, Inc. Copies of such Plan and Agreement
     are on file in the offices of ActivBiotics, Inc.

          (c) ESCROW OF SHARES. The Committee may require that the stock
certificates evidencing shares of Restricted Stock be held in custody by a
designated escrow agent (which may but need not be the Company) until the
restrictions thereon shall have lapsed, and that the Participant deliver a stock
power, endorsed in blank, relating to the Stock covered by such Award.

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                                        8


          (d) RESTRICTIONS AND RESTRICTION PERIOD. During the Restriction Period
applicable to shares of Restricted Stock, such shares shall be subject to
limitations on transferability and a Risk of Forfeiture arising on the basis of
such conditions related to the performance of services, Company or Affiliate
performance or otherwise as the Committee may determine and provide for in the
applicable Award Agreement. Any such Risk of Forfeiture may be waived or
terminated, or the Restriction Period shortened, at any time by the Committee on
such basis as it deems appropriate.

          (c) RIGHTS PENDING LAPSE OF RISK OF FORFEITURE OR FORFEITURE OF AWARD.
Except as otherwise provided in the Plan or the applicable Award Agreement, at
all times prior to lapse of any Risk of Forfeiture applicable to, or forfeiture
of, an Award of Restricted Stock, the Participant shall have all of the rights
of a stockholder of the Company, including the right to vote, and the right to
receive any dividends with respect to, the shares of Restricted Stock. The
Committee, as determined at the time of Award, may permit or require the payment
of cash dividends to be deferred and, if the Committee so determines, reinvested
in additional Restricted Stock to the extent shares are available under Section
4.

          (f) TERMINATION OF ASSOCIATION WITH THE COMPANY. Unless the Committee
shall provide otherwise for any Award of Restricted Stock, upon termination of a
Participant's employment or other association with the Company and its
Affiliates for any reason during the Restriction Period, including because of
the Participant's employer ceasing to be an Affiliate during the Restriction
Period, all shares of Restricted Stock still subject to Risk of Forfeiture shall
be forfeited or otherwise subject to return to or repurchase by the Company on
the terms specified in the Award Agreement; PROVIDED, HOWEVER, that military or
sick leave or other bona fide leave shall not be deemed a termination of
employment or other association, if it does not exceed the longer of ninety (90)
days or the period during which the absent Participant's reemployment rights, if
any, are guaranteed by statute or by contract.

          (g) LAPSE OF RESTRICTIONS. If and when the Restriction Period expires
without a prior forfeiture of the Restricted Stock, the certificates for such
shares shall be delivered to the Participant promptly if not theretofore so
delivered.

     7.3. STOCK GRANTS. Stock Grants shall be awarded solely in recognition of
significant contributions to the success of the Company or its Affiliates, in
lieu of compensation otherwise already due and in such other limited
circumstances as the Committee deems appropriate. Stock Grants shall be made
without forfeiture conditions of any kind.

     7.4. AWARDS TO PARTICIPANTS OUTSIDE THE UNITED STATES. The Committee may
modify the terms of any Award under the Plan granted to a Participant who is, at
the time of grant or during the term of the Award, resident or primarily
employed outside of the United States in any manner deemed by the Committee to
be necessary or appropriate in order that the Award shall conform to laws,
regulations, and customs of the country in which the Participant is then
resident or primarily employed, or so that the value and

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                                        9


other benefits of the Award to the Participant, as affected by foreign tax laws
and other restrictions applicable as a result of the Participant's residence or
employment abroad, shall be comparable to the value of such an Award to a
Participant who is resident or primarily employed in the United States. An Award
may be modified under this Section 7.4 in a manner that is inconsistent with the
express terms of the Plan, so long as such modifications will not contravene any
applicable law or regulation.

     8.   ADJUSTMENT PROVISIONS

     8.1. ADJUSTMENT FOR CORPORATE ACTIONS. All of the share numbers set forth
in the Plan reflect the capital structure of the Company as of September 28,
2001 (after giving effect to that certain reverse stock split pursuant to and as
set forth in the Company's Second Amended and Restated Certificate of
Incorporation filed with the Secretary of State of the State of Delaware on the
same date). Subject to Sections 8.2 and 8.3, if subsequent to that date the
outstanding shares of Common Stock (or any other securities covered by the Plan
by reason of the prior application of this Section) are increased, decreased, or
exchanged for a different number or kind of shares or other securities, or if
additional shares or new or different shares or other securities are distributed
with respect to shares of Common Stock or other securities, through merger,
consolidation, sale of all or substantially all the property of the Company,
reorganization, recapitalization, reclassification, stock dividend, stock split,
reverse stock split, or other distribution with respect to such shares of Common
Stock, or other securities, an appropriate and proportionate adjustment will be
made in (i) the maximum numbers and kinds of shares provided in Section 4, (ii)
the numbers and kinds of shares or other securities subject to the then
outstanding Awards, (iii) the exercise price for each share or other unit of any
other securities subject to then outstanding Options (without change in the
aggregate purchase price as to which such Options remain exercisable), and (iv)
the repurchase price of each share of Restricted Stock then subject to a Risk of
Forfeiture in the form of a Company repurchase right.

     8.2. TREATMENT IN ACQUISITIONS. Subject to any provisions of then
outstanding Awards granting greater rights to the holders thereof, in the event
of an Acquisition (a) any then outstanding Options shall Accelerate in full if
not assumed by the acquiring entity or replaced by comparable options to
purchase shares of the capital stock of the successor or acquiring entity or
parent thereof, and to the extent not assumed or replaced on the Acquisition
shall then (or after a reasonable period following the Acquisition, as
determined by the Committee) terminate to the extent not exercised and (b) any
then Restricted Stock shall Accelerate in full if the Company's rights to
reacquire such shares of Restricted Stock on occurrence of the applicable Risk
of Forfeiture with respect to those shares are not assigned to the acquiring
entity. As to any one or more outstanding Options and shares of Restricted Stock
which are not otherwise Accelerated in full by reason of such Acquisition, the
Committee may also, either in advance of an Acquisition or at the time thereof
and upon such terms as it may deem appropriate, provide for the Acceleration of
such outstanding Options and Restricted Stock in the event that the employment
of the Participants should subsequently terminate following the Acquisition.
Each outstanding Option that is assumed in connection with an Acquisition, or is

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                                       10


otherwise to continue in effect subsequent to the Acquisition, will be
appropriately adjusted, immediately after the Acquisition, as to the number and
class of securities and the price at which it may be exercised in accordance
with Section 8.1.

     8.3. CHANGE IN CONTROL. Subject to any provisions of then outstanding
Awards granting greater rights to the holders thereof, in the event of a Change
in Control (including a Change of Control which is an Acquisition), any
Restricted Stock Award still then subject to a Risk of Forfeiture and any
outstanding Option not then exercisable in full shall vest under the terms of
the Award. The preceding shall apply as well to shares of Restricted Stock the
repurchase rights of which are held by an acquiring entity, and outstanding
Options which are assumed by an acquiring entity or replaced by comparable
options to purchase shares of the capital stock of a successor or acquiring
entity or parent thereof, pursuant to Section 8.2. The Committee shall have the
discretion, exercisable either in advance of a Change in Control or at the time
thereof, to provide (upon such terms as it may deem appropriate) for (i) the
automatic Acceleration of one or more outstanding Options (including Options
that are assumed or replaced pursuant to Section 8.2) that do not otherwise
Accelerate by reason of the Change in Control, and/or (ii) the subsequent
termination of one or more of the Company's repurchase rights with respect to
Restricted Stock Awards that do not otherwise terminate at that time, in the
event that the employment of the respective grantees of such Awards should
subsequently terminate following such Change in Control.

     8.4. DISSOLUTION OR LIQUIDATION. Upon dissolution or liquidation of the
Company, other than as part of an Acquisition or similar transaction, each
outstanding Option shall terminate, but the Optionee (if at the time in the
employ of or otherwise associated with the Company or any of its Affiliates)
shall have the right, immediately prior to the dissolution or liquidation, to
exercise the Option to the extent exercisable on the date of dissolution or
liquidation.

     8.5. RELATED MATTERS. Any adjustment in Awards made pursuant to this
Section 8 shall be determined and made, if at all, by the Committee and shall
include any correlative modification of terms, including of Option exercise
prices, rates of vesting or exercisability, Risks of Forfeiture and applicable
repurchase prices for Restricted Stock, which the Committee may deem necessary
or appropriate so as to ensure the rights of the Participants in their
respective Awards are not substantially diminished nor enlarged as a result
of the adjustment and corporate action other than as expressly contemplated in
this Section 8. No fraction of a share shall be purchasable or deliverable upon
exercise, but in the event any adjustment hereunder of the number of shares
covered by an Award shall cause such number to include a fraction of a share,
such number of shares shall be adjusted to the nearest smaller whole number of
shares. No adjustment of an Option exercise price per share pursuant to this
Section 8 shall result in an exercise price which is less than the par value of
the Stock.

     9.   SETTLEMENT OF AWARDS

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     9.1. VIOLATION OF LAW. Notwithstanding any other provision of the Plan or
the relevant Award Agreement, if, at any time, in the reasonable opinion of the
Company, the issuance of shares of Common Stock covered by an Award may
constitute a violation of law, then the Company may delay such issuance and the
delivery of a certificate for such shares until (i) approval shall have been
obtained from such governmental agencies, other than the Securities and Exchange
Commission, as may be required under any applicable law, rule, or regulation and
(ii) in the case where such issuance would constitute a violation of a law
administered by or a regulation of the Securities and Exchange Commission, one
of the following conditions shall have been satisfied:

          (a) the shares are at the time of the issue of such shares effectively
registered under the Act; or

          (b) the Company shall have determined, on such basis as it deems
appropriate (including an opinion of counsel in form and substance satisfactory
to the Company) that the sale, transfer, assignment, pledge, encumbrance or
other disposition of such shares or such beneficial interest, as the case may
be, does not require registration under the Securities Act of 1933, as amended
or any applicable State securities laws.

The Company shall make all reasonable efforts to bring about the occurrence of
said events.

     9.2. CORPORATE RESTRICTIONS ON RIGHTS IN STOCK. Any Stock to be issued
pursuant to Awards granted under the Plan shall be subject to all restrictions
upon the transfer thereof which may be now or hereafter imposed by the charter,
certificate or articles, and by-laws, of the Company. Whenever Stock is to be
issued pursuant to an Award, if the Committee so directs at or after grant, the
Company shall be under no obligation to issue such shares until such time, if
ever, as the recipient of the Award (and any person who exercises any Option, in
whole or in part), shall have become a party to and bound by the Stockholders'
Agreement, if any. In the event of any conflict between the provisions of this
Plan and the provisions of the Stockholders' Agreement, the provisions of the
Stockholders' Agreement shall control except as required to fulfill the
intention that this Plan constitute an incentive stock option plan within the
meaning of Section 422 of the Code, but insofar as possible the provisions of
the Plan and such Agreement shall be construed so as to give full force and
effect to all such provisions.

     9.3. INVESTMENT REPRESENTATIONS. The Company shall be under no obligation
to issue any shares covered by any Award unless the shares to be issued pursuant
to Awards granted under the Plan have been effectively registered under the
Securities Act of 1933, as amended, or the Participant shall have made such
written representations to the Company (upon which the Company believes it may
reasonably rely) as the Company may deem necessary or appropriate for purposes
of confirming that the issuance of such shares will be exempt from the
registration requirements of that Act and any applicable state securities laws
and otherwise in compliance with all applicable laws, rules and regulations,
including but not limited to that the Participant is acquiring the shares for
his

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or her own account for the purpose of investment and not with a view to, or for
sale in connection with, the distribution of any such shares.

     9.4. REGISTRATION. If the Company shall deem it necessary or desirable to
register under the Securities Act of 1933, as amended or other applicable
statutes any shares of Stock issued or to be issued pursuant to Awards granted
under the Plan, or to qualify any such shares of Stock for exemption from the
Securities Act of 1933, as amended or other applicable statutes, then the
Company shall take such action at its own expense. The Company may require from
each recipient of an Award, or each holder of shares of Stock acquired pursuant
to the Plan, such information in writing for use in any registration statement,
prospectus, preliminary prospectus or offering circular as is reasonably
necessary for that purpose and may require reasonable indemnity to the Company
and its officers and directors from that holder against all losses, claims,
damage and liabilities arising from use of the information so furnished and
caused by any untrue statement of any material fact therein or caused by the
omission to state a material fact required to be stated therein or necessary to
make the statements therein not misleading in the light of the circumstances
under which they were made. In addition, the Company may require of any such
person that he or she agree that, without the prior written consent of the
Company or the managing underwriter in any public offering of shares of Stock,
he or she will not sell, make any short sale of, loan, grant any option for the
purchase of, pledge or otherwise encumber, or otherwise dispose of, any shares
of Common Stock during the 180 day period commencing on the effective date of
the registration statement relating to the underwritten public offering of
securities. Without limiting the generality of the foregoing provisions of this
Section 9.4, if in connection with any underwritten public offering of
securities of the Company the managing underwriter of such offering requires
that the Company's directors and officers enter into a lock-up agreement
containing provisions that are more restrictive than the provisions set forth in
the preceding sentence, then (a) each holder of shares of Stock acquired
pursuant to the Plan (regardless of whether such person has complied or complies
with the provisions of clause (b) below) shall be bound by, and shall be deemed
to have agreed to, the same lock-up terms as those to which the Company's
directors and officers are required to adhere; and (b) at the request of the
Company or such managing underwriter, each such person shall execute and deliver
a lock-up agreement in form and substance equivalent to that which is required
to be executed by the Company's directors and officers.

     9.5. PLACEMENT OF LEGENDS; STOP ORDERS; ETC. Each share of Common Stock to
be issued pursuant to Awards granted under the Plan may bear a reference to the
investment representation made in accordance with Section 9.3 in addition to any
other applicable restriction under the Plan, the terms of the Award and, if
applicable, under the Stockholders' Agreement and to the fact that no
registration statement has been filed with the Securities and Exchange
Commission in respect to such shares of Common Stock. All certificates for
shares of Common Stock or other securities delivered under the Plan shall be
subject to such stock transfer orders and other restrictions as the Committee
may deem advisable under the rules, regulations, and other requirements of any
stock exchange upon which the Common Stock is then listed, and any applicable
federal or

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state securities law, and the Committee may cause a legend or legends to be put
on any such certificates to make appropriate reference to such restrictions.

     9.6. TAX WITHHOLDING. Whenever shares of Stock are issued or to be issued
pursuant to Awards granted under the Plan, the Company shall have the right to
require the recipient to remit to the Company an amount sufficient to satisfy
federal, state, local or other withholding tax requirements if, when, and to the
extent required by law (whether so required to secure for the Company an
otherwise available tax deduction or otherwise) prior to the delivery of any
certificate or certificates for such shares. The obligations of the Company
under the Plan shall be conditional on satisfaction of all such withholding
obligations and the Company shall, to the extent permitted by law, have the
right to deduct any such taxes from any payment of any kind otherwise due to the
recipient of an Award.

     10. RESERVATION OF STOCK. The Company shall at all times during the term of
the Plan and any outstanding Options granted hereunder reserve or otherwise keep
available such number of shares of Stock as will be sufficient to satisfy the
requirements of the Plan (if then in effect) and the Options and shall pay all
fees and expenses necessarily incurred by the Company in connection therewith.

     11. NO SPECIAL EMPLOYMENT OR OTHER RIGHTS. Nothing contained in the Plan or
in any Award Agreement shall confer upon any recipient of an Award any right
with respect to the continuation of his or her employment or other association
with the Company (or any Affiliate), or interfere in any way with the right of
the Company (or any Affiliate), subject to the terms of any separate employment
or consulting agreement or provision of law or corporate charter, certificate or
articles, or by-laws, to the contrary, at any time to terminate such employment
or consulting agreement or to increase or decrease, or otherwise adjust, the
other terms and conditions of the recipient's employment or other association
with the Company and its Affiliates.

     12. NONEXCLUSIVITY OF THE PLAN. Neither the adoption of the Plan by the
Board nor the submission of the Plan to the stockholders of the Company shall be
construed as creating any limitations on the power of the Board to adopt such
other incentive arrangements as it may deem desirable, including without
limitation, the granting of stock options and restricted stock other than under
the Plan, and such arrangements may be either applicable generally or only in
specific cases.

     13. TERMINATION AND AMENDMENT OF THE PLAN. The Board may at any time
terminate the Plan or make such modifications of the Plan as it shall deem
advisable. Unless the Board otherwise expressly provides, no amendment of the
Plan shall affect the terms of any Award outstanding on the date of such
amendment. In any case, no termination or amendment of the Plan may, without the
consent of any recipient of an Award granted hereunder, adversely affect the
rights of the recipient under such Award.

     The Committee may amend the terms of any Award theretofore granted,
prospectively or retroactively, provided that the Award as amended is consistent
with the

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                                       14


terms of the Plan, but no such amendment shall impair the rights of the
recipient of such Award without his or her consent.

     14. NOTICES AND OTHER COMMUNICATIONS. Any notice, demand, request or other
communication hereunder to any party shall be deemed to be sufficient if
contained in a written instrument delivered in person or duly sent by first
class registered, certified or overnight mail, postage prepaid, or telecopied
with a confirmation copy by regular, certified or overnight mail, addressed or
telecopied, as the case may be, (i) if to the recipient of an Award, at his or
her residence address last filed with the Company and (ii) if to the Company, at
its principal place of business, addressed to the attention of its Treasurer, or
to such other address or telecopier number, as the case may be, as the addressee
may have designated by notice to the addressor. All such notices, requests,
demands and other communications shall be deemed to have been received: (i) in
the case of personal delivery, on the date of such delivery; (ii) in the case of
mailing, when received by the addressee; and (iii) in the case of facsimile
transmission, when confirmed by facsimile machine report.

     15. GOVERNING LAW. The Plan and all Award Agreements and actions taken
thereunder shall be governed, interpreted and enforced in accordance with the
laws of the Commonwealth of Massachusetts, without regard to the conflict of
laws principles thereof.

                                      * * *

     The following does not form part of this Plan but is included solely for
informational purposes:

Date of Board Approval:                             August 28, 2001
Date of Shareholder Approval:                       September 28, 2001
Date of Board Approval of First Amendment:          April 30, 2003
Date of Shareholder Approval of First Amendment:    April 30, 2003
Date of Board Approval of Second Amendment:         January 22, 2004
Date of Shareholder Approval of Second Amendment:   January 22, 2004