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                                                                   EXHIBIT 10.21



                          As adopted by the Board of Directors on March 31, 2004
                               As approved by the shareholders on March 31, 2004
                            As amended by the Board of Directors on June 3, 2004

                                 ARCHEMIX CORP.

                               AMENDED & RESTATED
                2001 EMPLOYEE, DIRECTOR AND CONSULTANT STOCK PLAN

1.   DEFINITIONS.

     Unless otherwise specified or unless the context otherwise requires, the
     following terms, as used in this Archemix Corp. 2001 Employee, Director and
     Consultant Stock Plan, have the following meanings:

          Administrator means the Board of Directors, unless it has delegated
          power to act on its behalf to the Committee, in which case the
          Administrator means the Committee.

          Affiliate means a corporation which, for purposes of Section 424 of
          the Code, is a parent or subsidiary of the Company, direct or
          indirect.

          Board of Directors means the Board of Directors of the Company.

          Code means the United States Internal Revenue Code of 1986, as
          amended.

          Committee means the committee of the Board of Directors to which the
          Board of Directors has delegated power to act under or pursuant to the
          provisions of the Plan.

          Common Stock means shares of the Company's common stock, $.001 par
          value per share.

          Company means Archemix Corp., a Delaware corporation.

          Disability or Disabled means permanent and total disability as defined
          in Section 22(e)(3) of the Code.

          Fair Market Value of a Share of Common Stock means:

          (1) If the Common Stock is listed on a national securities exchange or
          traded in the over-the-counter market and sales prices are regularly
          reported for the Common Stock, the closing or last price of the Common
          Stock on the Composite

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          Tape or other comparable reporting system for the trading day
          immediately preceding the applicable date;

          (2) If the Common Stock is not traded on a national securities
          exchange but is traded on the over-the-counter market, if sales prices
          are not regularly reported for the Common Stock for the trading day
          referred to in clause (1), and if bid and asked prices for the Common
          Stock are regularly reported, the mean between the bid and the asked
          price for the Common Stock at the close of trading in the
          over-the-counter market for the trading day on which Common Stock was
          traded immediately preceding the applicable date; and

          (3) If the Common Stock is neither listed on a national securities
          exchange nor traded in the over-the-counter market, such value as the
          Administrator, in good faith, shall determine.

          ISO means an option meant to qualify as an incentive stock option
          under Section 422 of the Code.

          Key Employee means an employee of the Company or of an Affiliate
          (including, without limitation, an employee who is also serving as an
          officer or director of the Company or of an Affiliate), designated by
          the Administrator to be eligible to be granted one or more Stock
          Rights under the Plan.

          Non-Qualified Option means an option which is not intended to qualify
          as an ISO.

          Option means an ISO or Non-Qualified Option granted under the Plan.

          Option Agreement means an agreement between the Company and a
          Participant delivered pursuant to the Plan, in such form as the
          Administrator shall approve.

          Participant means a Key Employee, director or consultant to whom one
          or more Stock Rights are granted under the Plan. As used herein,
          "Participant" shall include "Participant's Survivors" where the
          context requires.

          Plan means this Archemix Corp. 2001 Employee, Director and Consultant
          Stock Plan.

          Shares means shares of the Common Stock as to which Stock Rights have
          been or may be granted under the Plan or any shares of capital stock
          into which the Shares are changed or for which they are exchanged
          within the provisions of Paragraph 3 of the Plan. The Shares issued
          under the Plan may be authorized and unissued shares or shares held by
          the Company in its treasury, or both.

          Stock Grant means a grant by the Company of Shares under the Plan.


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          Stock Grant Agreement means an agreement between the Company and a
          Participant delivered pursuant to the Plan, in such form as the
          Administrator shall approve.

          Stock Right means a right to Shares of the Company granted pursuant to
          the Plan -- an ISO, a Non-Qualified Option or a Stock Grant.

          Survivors means a deceased Participant's legal representatives and/or
          any person or persons who acquired the Participant's rights to a Stock
          Right by will or by the laws of descent and distribution.

2.   PURPOSES OF THE PLAN.

     The Plan is intended to encourage ownership of Shares by Key Employees and
directors of and certain consultants to the Company in order to attract such
people, to induce them to work for the benefit of the Company or of an Affiliate
and to provide additional incentive for them to promote the success of the
Company or of an Affiliate. The Plan provides for the granting of ISOs,
Non-Qualified Options and Stock Grants.

3.   SHARES SUBJECT TO THE PLAN.

     The number of Shares which may be issued from time to time pursuant to this
Plan shall be Seventeen Million Three Hundred Forty Nine Thousand Four Hundred
Twenty Two (17,349,422), or the equivalent of such number of Shares after the
Administrator, in its sole discretion, has interpreted the effect of any stock
split, stock dividend, combination, recapitalization or similar transaction in
accordance with Paragraph 23 of the Plan.

     If an Option ceases to be "outstanding", in whole or in part, or if the
Company shall reacquire any Shares issued pursuant to a Stock Grant, the Shares
which were subject to such Option and any Shares so reacquired by the Company
shall be available for the granting of other Stock Rights under the Plan. Any
Option shall be treated as "outstanding" until such Option is exercised in full,
or terminates or expires under the provisions of the Plan, or by agreement of
the parties to the pertinent Option Agreement.

4.   ADMINISTRATION OF THE PLAN.

     The Administrator of the Plan will be the Board of Directors, except to the
extent the Board of Directors delegates its authority to the Committee, in which
case the Committee shall be the Administrator. Subject to the provisions of the
Plan, the Administrator is authorized to:

     a.   Interpret the provisions of the Plan or of any Option or Stock Grant
          and to make all rules and determinations which it deems necessary or
          advisable for the administration of the Plan;


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     b.   Determine which employees of the Company or of an Affiliate shall be
          designated as Key Employees and which of the Key Employees, directors
          and consultants shall be granted Stock Rights;

     c.   Determine the number of Shares for which a Stock Right or Stock Rights
          shall be granted;

     d.   Specify the terms and conditions upon which a Stock Right or Stock
          Rights may be granted; and

     e.   Adopt any sub-plans applicable to residents of any specified
          jurisdiction as it deems necessary or appropriate in order to comply
          with or take advantage of any tax laws applicable to the Company or to
          Plan Participants or to otherwise facilitate the administration of the
          Plan, which sub-plans may include additional restrictions or
          conditions applicable to Options or Shares acquired upon exercise of
          Options; provided, however, that all such interpretations, rules,
          determinations, terms and conditions shall be made and prescribed in
          the context of preserving the tax status under Section 422 of the Code
          of those Options which are designated as ISOs. Subject to the
          foregoing, the interpretation and construction by the Administrator of
          any provisions of the Plan or of any Stock Right granted under it
          shall be final, unless otherwise determined by the Board of Directors,
          if the Administrator is the Committee. In addition, if the
          Administrator is the Committee, the Board of Directors may take any
          action under the Plan that would otherwise be the responsibility of
          the Committee.

     If permissible under applicable law, the Board of Directors or the
Committee may allocate all or any portion of its responsibilities and powers to
any one or more of its members and may delegate all or any portion of its
responsibilities and powers to any other person selected by it. Any such
allocation or delegation may be revoked by the Board of Directors or the
Committee at any time.

5.   ELIGIBILITY FOR PARTICIPATION.

     The Administrator will, in its sole discretion, name the Participants in
the Plan, provided, however, that each Participant must be a Key Employee,
director or consultant of the Company or of an Affiliate at the time a Stock
Right is granted. Notwithstanding the foregoing, the Administrator may authorize
the grant of a Stock Right to a person not then an employee, director or
consultant of the Company or of an Affiliate; provided, however, that the actual
grant of such Stock Right shall be conditioned upon such person becoming
eligible to become a Participant at or prior to the time of the delivery of the
Agreement evidencing such Stock Right. ISOs may be granted only to Key
Employees. Non-Qualified Options and Stock Grants may be granted to any Key
Employee, director or consultant of the Company or an Affiliate. The granting of
any Stock Right to any individual shall neither entitle that individual to, nor
disqualify him or her from, participation in any other grant of Stock Rights.


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6.   TERMS AND CONDITIONS OF OPTIONS.

     Each Option shall be set forth in writing in an Option Agreement, duly
executed by the Company and, to the extent required by law or requested by the
Company, by the Participant. The Administrator may provide that Options be
granted subject to such terms and conditions, consistent with the terms and
conditions specifically required under this Plan, as the Administrator may deem
appropriate including, without limitation, subsequent approval by the
shareholders of the Company of this Plan or any amendments thereto. The Option
Agreements shall be subject to at least the following terms and conditions:

     A.   Non-Qualified Options: Each Option intended to be a Non-Qualified
          Option shall be subject to the terms and conditions which the
          Administrator determines to be appropriate and in the best interest of
          the Company, subject to the following minimum standards for any such
          Non-Qualified Option:

          a.   Option Price: Each Option Agreement shall state the option price
               (per share) of the Shares covered by each Option, which option
               price shall be determined by the Administrator but shall not be
               less than the par value per share of Common Stock.

          b.   Each Option Agreement shall state the number of Shares to which
               it pertains;

          c.   Each Option Agreement shall state the date or dates on which it
               first is exercisable and the date after which it may no longer be
               exercised, and may provide that the Option rights accrue or
               become exercisable in installments over a period of months or
               years, or upon the occurrence of certain conditions or the
               attainment of stated goals or events; and

          d.   Exercise of any Option may be conditioned upon the Participant's
               execution of a Share purchase agreement in form satisfactory to
               the Administrator providing for certain protections for the
               Company and its other shareholders, including requirements that:

               i.   The Participant's or the Participant's Survivors' right to
                    sell or transfer the Shares may be restricted; and

               ii.  The Participant or the Participant's Survivors may be
                    required to execute letters of investment intent and must
                    also acknowledge that the Shares will bear legends noting
                    any applicable restrictions.


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     B.   ISOs: Each Option intended to be an ISO shall be issued only to a Key
          Employee and be subject to the following terms and conditions, with
          such additional restrictions or changes as the Administrator
          determines are appropriate but not in conflict with Section 422 of the
          Code and relevant regulations and rulings of the Internal Revenue
          Service:

          a.   Minimum standards: The ISO shall meet the minimum standards
               required of Non-Qualified Options, as described in Paragraph 6(A)
               above, except clauses (a) thereunder.

          b.   Option Price: Immediately before the Option is granted, if the
               Participant owns, directly or by reason of the applicable
               attribution rules in Section 424(d) of the Code:

               i.   Ten percent (10%) or less of the total combined voting power
                    of all classes of stock of the Company or an Affiliate, the
                    Option price per share of the Shares covered by each Option
                    shall not be less than one hundred percent (100%) of the
                    Fair Market Value per share of the Shares on the date of the
                    grant of the Option.

               ii.  More than ten percent (10%) of the total combined voting
                    power of all classes of stock of the Company or an
                    Affiliate, the Option price per share of the Shares covered
                    by each Option shall not be less than one hundred ten
                    percent (110%) of the said Fair Market Value on the date of
                    grant.

          c.   Term of Option: For Participants who own

               i.   Ten percent (10%) or less of the total combined voting power
                    of all classes of stock of the Company or an Affiliate, each
                    Option shall terminate not more than ten (10) years from the
                    date of the grant or at such earlier time as the Option
                    Agreement may provide.

               ii.  More than ten percent (10%) of the total combined voting
                    power of all classes of stock of the Company or an
                    Affiliate, each Option shall terminate not more than five
                    (5) years from the date of the grant or at such earlier time
                    as the Option Agreement may provide.

          d.   Limitation on Yearly Exercise: The Option Agreements shall
               restrict the amount of Options which may be exercisable in any
               calendar year (under this or any other ISO plan of the Company or
               an Affiliate) so that the aggregate Fair Market Value (determined
               at the time each ISO is granted) of the stock with respect to
               which ISOs are exercisable for the first time by the Participant
               in any calendar year does not exceed one hundred thousand dollars
               ($100,000), provided that this subparagraph (d) shall have no
               force


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               or effect if its inclusion in the Plan is not necessary for
               Options issued as ISOs to qualify as ISOs pursuant to Section
               422(d) of the Code.

7.   TERMS AND CONDITIONS OF STOCK GRANTS.

     Each offer of a Stock Grant to a Participant shall state the date prior to
which the Stock Grant must be accepted by the Participant, and the principal
terms of each Stock Grant shall be set forth in a Stock Grant Agreement, duly
executed by the Company and, to the extent required by law or requested by the
Company, by the Participant. The Stock Grant Agreement shall be in a form
approved by the Administrator and shall contain terms and conditions which the
Administrator determines to be appropriate and in the best interest of the
Company, subject to the following minimum standards:

     (a)  Each Stock Grant Agreement shall state the purchase price (per share),
          if any, of the Shares covered by each Stock Grant, which purchase
          price shall be determined by the Administrator but shall not be less
          than the minimum consideration required by Delaware General
          Corporation Law on the date of the grant of the Stock Grant;

     (b)  Each Stock Grant Agreement shall state the number of Shares to which
          the Stock Grant pertains; and

     (c)  Each Stock Grant Agreement shall include the terms of any right of the
          Company to reacquire the Shares subject to the Stock Grant, including
          the time and events upon which such rights shall accrue and the
          purchase price therefore, if any.

8.   EXERCISE OF OPTIONS AND ISSUE OF SHARES.

     An Option (or any part or installment thereof) shall be exercised by giving
written notice to the Company at its principal executive office address,
together with provision for payment of the full purchase price in accordance
with this Paragraph for the Shares as to which the Option is being exercised,
and upon compliance with any other condition(s) set forth in the Option
Agreement. Such written notice shall be signed by the person exercising the
Option, shall state the number of Shares with respect to which the Option is
being exercised and shall contain any representation required by the Plan or the
Option Agreement. Payment of the purchase price for the Shares as to which such
Option is being exercised shall be made (a) in United States dollars in cash or
by check, or (b) at the discretion of the Administrator, through delivery of
shares of Common Stock having a Fair Market Value equal as of the date of the
exercise to the cash exercise price of the Option, or (c) at the discretion of
the Administrator, by having the Company retain from the shares otherwise
issuable upon exercise of the Option, a number of shares having a Fair Market
Value equal as of the date of exercise to the exercise price of the Option, or
(d) at the discretion of the Administrator, by delivery of the grantee's
personal recourse note bearing interest payable not less than annually at no
less than 100% of the applicable Federal rate, as defined in Section 1274(d) of
the Code, or (e) at the discretion of the Administrator, in


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accordance with a cashless exercise program established with a securities
brokerage firm, and approved by the Administrator, or (f) at the discretion of
the Administrator, by any combination of (a), (b), (c), (d) and (e) above.
Notwithstanding the foregoing, the Administrator shall accept only such payment
on exercise of an ISO as is permitted by Section 422 of the Code.

     The Company shall then reasonably promptly deliver the Shares as to which
such Option was exercised to the Participant (or to the Participant's Survivors,
as the case may be). In determining what constitutes "reasonably promptly," it
is expressly understood that the issuance and delivery of the Shares may be
delayed by the Company in order to comply with any law or regulation (including,
without limitation, state securities or "blue sky" laws) which requires the
Company to take any action with respect to the Shares prior to their issuance.
The Shares shall, upon delivery, be evidenced by an appropriate certificate or
certificates for fully paid, non-assessable Shares.

     The Administrator shall have the right to accelerate the date of exercise
of any installment of any Option; provided that the Administrator shall not
accelerate the exercise date of any installment of any Option granted to any Key
Employee as an ISO (and not previously converted into a Non-Qualified Option
pursuant to Paragraph 26) if such acceleration would violate the annual vesting
limitation contained in Section 422(d) of the Code, as described in Paragraph
6.B.d.

     The Administrator may, in its discretion, amend any term or condition of an
outstanding Option provided (i) such term or condition as amended is permitted
by the Plan, (ii) any such amendment shall be made only with the consent of the
Participant to whom the Option was granted, or in the event of the death of the
Participant, the Participant's Survivors, if the amendment is adverse to the
Participant, and (iii) any such amendment of any ISO shall be made only after
the Administrator, after consulting the counsel for the Company, determines
whether such amendment would constitute a "modification" of any Option which is
an ISO (as that term is defined in Section 424(h) of the Code) or would cause
any adverse tax consequences for the holder of such ISO.

9.   ACCEPTANCE OF STOCK GRANT AND ISSUE OF SHARES.

     A Stock Grant (or any part or installment thereof) shall be accepted by
executing the Stock Grant Agreement and delivering it to the Company at its
principal office address, together with provision for payment of the full
purchase price, if any, in accordance with this Paragraph for the Shares as to
which such Stock Grant is being accepted, and upon compliance with any other
conditions set forth in the Stock Grant Agreement. Payment of the purchase price
for the Shares as to which such Stock Grant is being accepted shall be made (a)
in United States dollars in cash or by check, or (b) at the discretion of the
Administrator, through delivery of shares of Common Stock having a fair market
value equal as of the date of acceptance of the Stock Grant to the purchase
price of the Stock Grant determined in good faith by the Administrator, or (c)
at the discretion of the Administrator, by delivery of the grantee's personal
recourse note bearing interest payable not less than annually at no less than
100% of the applicable Federal rate, as


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defined in Section 1274(d) of the Code, or (d) at the discretion of the
Administrator, by any combination of (a), (b) and (c) above.

     The Company shall then reasonably promptly deliver the Shares as to which
such Stock Grant was accepted to the Participant (or to the Participant's
Survivors, as the case may be), subject to any escrow provision set forth in the
Stock Grant Agreement. In determining what constitutes "reasonably promptly," it
is expressly understood that the issuance and delivery of the Shares may be
delayed by the Company in order to comply with any law or regulation (including,
without limitation, state securities or "blue sky" laws) which requires the
Company to take any action with respect to the Shares prior to their issuance.

     The Administrator may, in its discretion, amend any term or condition of an
outstanding Stock Grant or Stock Grant Agreement provided (i) such term or
condition as amended is permitted by the Plan, and (ii) any such amendment shall
be made only with the consent of the Participant to whom the Stock Grant was
made, if the amendment is adverse to the Participant.

10.  RIGHTS AS A SHAREHOLDER.

     No Participant to whom a Stock Right has been granted shall have rights as
a shareholder with respect to any Shares covered by such Stock Right, except
after due exercise of the Option or acceptance of the Stock Grant and tender of
the full purchase price, if any, for the Shares being purchased pursuant to such
exercise or acceptance and registration of the Shares in the Company's share
register in the name of the Participant.

11.  ASSIGNABILITY AND TRANSFERABILITY OF STOCK RIGHTS.

     By its terms, a Stock Right granted to a Participant shall not be
transferable by the Participant other than (i) by will or by the laws of descent
and distribution, or (ii) as otherwise determined by the Administrator and set
forth in the applicable Option Agreement or Stock Grant Agreement. The
designation of a beneficiary of a Stock Right by a Participant, with the prior
approval of the Administrator and in such form as the Administrator shall
prescribe, shall not be deemed a transfer prohibited by this Paragraph. Except
as provided above, a Stock Right shall only be exercisable or may only be
accepted, during the Participant's lifetime, by such Participant (or by his or
her legal representative) and shall not be assigned, pledged or hypothecated in
any way (whether by operation of law or otherwise) and shall not be subject to
execution, attachment or similar process. Any attempted transfer, assignment,
pledge, hypothecation or other disposition of any Stock Right or of any rights
granted thereunder contrary to the provisions of this Plan, or the levy of any
attachment or similar process upon a Stock Right, shall be null and void.


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12.  EFFECT ON OPTIONS OF TERMINATION OF SERVICE OTHER THAN "FOR CAUSE" OR DEATH
     OR DISABILITY.

     Except as otherwise provided in the pertinent Option Agreement in the event
of a termination of service (whether as an employee, director or consultant)
with the Company or an Affiliate before the Participant has exercised an Option,
the following rules apply:

     a.   A Participant who ceases to be an employee, director or consultant of
          the Company or of an Affiliate (for any reason other than termination
          "for cause", Disability, or death for which events there are special
          rules in Paragraphs 13, 14, and 15, respectively), may exercise any
          Option granted to him or her to the extent that the Option is
          exercisable on the date of such termination of service, but only
          within such term as the Administrator has designated in the pertinent
          Option Agreement.

     b.   Except as provided in Subparagraph (c) below, or Paragraph 14 or 15,
          in no event may an Option Agreement provide, if an Option is intended
          to be an ISO, that the time for exercise be later than three (3)
          months after the Participant's termination of employment.

     c.   The provisions of this Paragraph, and not the provisions of Paragraph
          14 or 15, shall apply to a Participant who subsequently becomes
          Disabled or dies after the termination of employment, director status
          or consultancy, provided, however, in the case of a Participant's
          Disability or death within three (3) months after the termination of
          employment, director status or consultancy, the Participant or the
          Participant's Survivors may exercise the Option within one (1) year
          after the date of the Participant's termination of employment, but in
          no event after the date of expiration of the term of the Option.

     d.   Notwithstanding anything herein to the contrary, if subsequent to a
          Participant's termination of employment, termination of director
          status or termination of consultancy, but prior to the exercise of an
          Option, the Board of Directors determines that, either prior or
          subsequent to the Participant's termination, the Participant engaged
          in conduct which would constitute "cause", then such Participant shall
          forthwith cease to have any right to exercise any Option.

     e.   A Participant to whom an Option has been granted under the Plan who is
          absent from work with the Company or with an Affiliate because of
          temporary disability (any disability other than a permanent and total
          Disability as defined in Paragraph 1 hereof), or who is on leave of
          absence for any purpose, shall not, during the period of any such
          absence, be deemed, by virtue of such absence alone, to have
          terminated such Participant's employment, director status or
          consultancy with the Company or with an Affiliate, except as the
          Administrator may otherwise expressly provide.


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     f.   Except as required by law or as set forth in the pertinent Option
          Agreement, Options granted under the Plan shall not be affected by any
          change of a Participant's status within or among the Company and any
          Affiliates, so long as the Participant continues to be an employee,
          director or consultant of the Company or any Affiliate.

13.  EFFECT ON OPTIONS OF TERMINATION OF SERVICE "FOR CAUSE".

     Except as otherwise provided in the pertinent Option Agreement, the
following rules apply if the Participant's service (whether as an employee,
director or consultant) with the Company or an Affiliate is terminated "for
cause" prior to the time that all his or her outstanding Options have been
exercised:

     a.   All outstanding and unexercised Options as of the time the Participant
          is notified his or her service is terminated "for cause" will
          immediately be forfeited.

     b.   For purposes of this Plan, "cause" shall include (and is not limited
          to):

          (i)  a violation of an important Company policy, the neglect of a
               Participant's duties or the gross or willful failure of a
               Participant to perform his or her duties hereunder, which is not
               cured after five days notice.

          (ii) dishonesty, embezzlement, gross negligence, willful misconduct,
               neglect, theft, fraud or breach of fiduciary duty to the Company;

          (iii) violation of federal or state securities laws;

          (iv) breach of an employment, consulting or other agreement
               (including, without limitation, the Employee Noncompetition,
               Nondisclosure and Development Agreement between a Participant and
               the Company, which breach harms, damages, causes loss to or
               injures the business or reputation of the Company;

          (v)  the unauthorized disclosure of any trade secret or confidential
               information of the Company;

          (vi) the commission of an act which constitutes unfair competition
               with the Company or which induces any customer or supplier to
               breach a contract with the Company;

          (vii) an act by a Participant which creates adverse publicity for the
               Company; or

          (viii) the conviction of a Participant for the commission of any
               felony including a pleas of guilty or nolo contendere.


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     The determination of the Administrator as to the existence of "cause" will
be conclusive on the Participant and the Company.

     c.   "Cause" is not limited to events which have occurred prior to a
          Participant's termination of service, nor is it necessary that the
          Administrator's finding of "cause" occur prior to termination. If the
          Administrator determines, subsequent to a Participant's termination of
          service but prior to the exercise of an Option, that either prior or
          subsequent to the Participant's termination the Participant engaged in
          conduct which would constitute "cause", then the right to exercise any
          Option is forfeited.

     d.   Any definition in an agreement between the Participant and the Company
          or an Affiliate, which contains a conflicting definition of "cause"
          for termination and which is in effect at the time of such
          termination, shall supersede the definition in this Plan with respect
          to such Participant.

14.  EFFECT ON OPTIONS OF TERMINATION OF SERVICE FOR DISABILITY.

     Except as otherwise provided in the pertinent Option Agreement, a
Participant who ceases to be an employee, director or consultant of the Company
or of an Affiliate by reason of Disability may exercise any Option granted to
such Participant:

     a.   To the extent exercisable but not exercised on the date of Disability;
          and

     b.   In the event rights to exercise the Option accrue periodically, to the
          extent of a pro rata portion of any additional rights as would have
          accrued had the Participant not become Disabled prior to the end of
          the accrual period which next ends following the date of Disability.
          The proration shall be based upon the number of days of such accrual
          period prior to the date of Disability.

     A Disabled Participant may exercise such rights only within the period
ending one (1) year after the date of the Participant's termination of
employment, directorship or consultancy, as the case may be, notwithstanding
that the Participant might have been able to exercise the Option as to some or
all of the Shares on a later date if the Participant had not become disabled and
had continued to be an employee, director or consultant or, if earlier, within
the originally prescribed term of the Option.

     The Administrator shall make the determination both of whether Disability
has occurred and the date of its occurrence (unless a procedure for such
determination is set forth in another agreement between the Company and such
Participant, in which case such procedure shall be used for such determination).
If requested, the Participant shall be examined by a physician selected or
approved by the Administrator, the cost of which examination shall be paid for
by the Company.


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15.  EFFECT ON OPTIONS OF DEATH WHILE AN EMPLOYEE, DIRECTOR OR CONSULTANT.

     Except as otherwise provided in the pertinent Option Agreement, in the
event of the death of a Participant while the Participant is an employee,
director or consultant of the Company or of an Affiliate, such Option may be
exercised by the Participant's Survivors:

     a.   To the extent exercisable but not exercised on the date of death; and

     b.   In the event rights to exercise the Option accrue periodically, to the
          extent of a pro rata portion of any additional rights which would have
          accrued had the Participant not died prior to the end of the accrual
          period which next ends following the date of death. The proration
          shall be based upon the number of days of such accrual period prior to
          the Participant's death.

     If the Participant's Survivors wish to exercise the Option, they must take
all necessary steps to exercise the Option within one (1) year after the date of
death of such Participant, notwithstanding that the decedent might have been
able to exercise the Option as to some or all of the Shares on a later date if
he or she had not died and had continued to be an employee, director or
consultant or, if earlier, within the originally prescribed term of the Option.

16.  EFFECT OF TERMINATION OF SERVICE ON STOCK GRANTS.

     In the event of a termination of service (whether as an employee, director
or consultant) with the Company or an Affiliate for any reason before the
Participant has accepted a Stock Grant, such offer shall terminate.

     For purposes of this Paragraph 16 and Paragraph 17 below, a Participant to
whom a Stock Grant has been offered under the Plan who is absent from work with
the Company or with an Affiliate because of temporary disability (any disability
other than a permanent and total Disability as defined in Paragraph 1 hereof),
or who is on leave of absence for any purpose, shall not, during the period of
any such absence, be deemed, by virtue of such absence alone, to have terminated
such Participant's employment, director status or consultancy with the Company
or with an Affiliate, except as the Administrator may otherwise expressly
provide.

     In addition, for purposes of this Paragraph 16 and Paragraph 17 below, any
change of employment or other service within or among the Company and any
Affiliates shall not be treated as a termination of employment, director status
or consultancy so long as the Participant continues to be an employee, director
or consultant of the Company or any Affiliate.


                                       13

<PAGE>

17.  EFFECT ON STOCK GRANTS OF TERMINATION OF SERVICE OTHER THAN "FOR CAUSE" OR
     DEATH OR DISABILITY.

     Except as otherwise provided in the pertinent Stock Grant Agreement, in the
event of a termination of service (whether as an employee, director or
consultant), other than termination "for cause," Disability, or death for which
events there are special rules in Paragraphs 18, 19, and 20, respectively,
before all Company rights of repurchase shall have lapsed, then the Company
shall have the right to repurchase that number of Shares subject to a Stock
Grant as to which the Company's repurchase rights have not lapsed.

18.  EFFECT ON STOCK GRANTS OF TERMINATION OF SERVICE "FOR CAUSE".

     Except as otherwise provided in the pertinent Stock Grant Agreement, the
following rules apply if the Participant's service (whether as an employee,
director or consultant) with the Company or an Affiliate is terminated "for
cause":

     a.   All Shares subject to any Stock Grant shall be immediately subject to
          repurchase by the Company at the purchase price, if any, thereof.

     b.   For purposes of this Plan, "cause" shall include (and is not limited
          to) dishonesty with respect to the employer, insubordination,
          substantial malfeasance or non-feasance of duty, unauthorized
          disclosure of confidential information, and conduct substantially
          prejudicial to the business of the Company or any Affiliate. The
          determination of the Administrator as to the existence of "cause" will
          be conclusive on the Participant and the Company.

     c.   "Cause" is not limited to events which have occurred prior to a
          Participant's termination of service, nor is it necessary that the
          Administrator's finding of "cause" occur prior to termination. If the
          Administrator determines, subsequent to a Participant's termination of
          service, that either prior or subsequent to the Participant's
          termination the Participant engaged in conduct which would constitute
          "cause," then the Company's right to repurchase all of such
          Participant's Shares shall apply.

     d.   Any definition in an agreement between the Participant and the Company
          or an Affiliate, which contains a conflicting definition of "cause"
          for termination and which is in effect at the time of such
          termination, shall supersede the definition in this Plan with respect
          to such Participant.

19.  EFFECT ON STOCK GRANTS OF TERMINATION OF SERVICE FOR DISABILITY.

     Except as otherwise provided in the pertinent Stock Grant Agreement, the
following rules apply if a Participant ceases to be an employee, director or
consultant of the Company or of an


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<PAGE>

Affiliate by reason of Disability: to the extent the Company's rights of
repurchase have not lapsed on the date of Disability, they shall be exercisable;
provided, however, that in the event such rights of repurchase lapse
periodically, such rights shall lapse to the extent of a pro rata portion of the
Shares subject to such Stock Grant as would have lapsed had the Participant not
become Disabled prior to the end of the vesting period which next ends following
the date of Disability. The proration shall be based upon the number of days of
such vesting period prior to the date of Disability.

     The Administrator shall make the determination both of whether Disability
has occurred and the date of its occurrence (unless a procedure for such
determination is set forth in another agreement between the Company and such
Participant, in which case such procedure shall be used for such determination).
If requested, the Participant shall be examined by a physician selected or
approved by the Administrator, the cost of which examination shall be paid for
by the Company.

20.  EFFECT ON STOCK GRANTS OF DEATH WHILE AN EMPLOYEE, DIRECTOR OR CONSULTANT.

     Except as otherwise provided in the pertinent Stock Grant Agreement, the
following rules apply in the event of the death of a Participant while the
Participant is an employee, director or consultant of the Company or of an
Affiliate: to the extent the Company's rights of repurchase have not lapsed on
the date of death, they shall be exercisable; provided, however, that in the
event such rights of repurchase lapse periodically, such rights shall lapse to
the extent of a pro rata portion of the Shares subject to such Stock Grant as
would have lapsed had the Participant not died prior to the end of the vesting
period which next ends following the date of death. The proration shall be based
upon the number of days of such vesting period prior to the Participant's death.

21.  PURCHASE FOR INVESTMENT.

     Unless the offering and sale of the Shares to be issued upon the particular
exercise or acceptance of a Stock Right shall have been effectively registered
under the Securities Act of 1933, as now in force or hereafter amended (the
"1933 Act"), the Company shall be under no obligation to issue the Shares
covered by such exercise unless and until the following conditions have been
fulfilled:

     a.   The person(s) who exercise(s) or accept(s) such Stock Right shall
          warrant to the Company, prior to the receipt of such Shares, that such
          person(s) are acquiring such Shares for their own respective accounts,
          for investment, and not with a view to, or for sale in connection
          with, the distribution of any such Shares, in which event the
          person(s) acquiring such Shares shall be bound by the provisions of
          the following legend which shall be endorsed upon the certificate(s)
          evidencing their Shares issued pursuant to such exercise or such
          grant:


                                       15

<PAGE>

               "The shares represented by this certificate have been taken for
               investment and they may not be sold or otherwise transferred by
               any person, including a pledgee, unless (1) either (a) a
               Registration Statement with respect to such shares shall be
               effective under the Securities Act of 1933, as amended, or (b)
               the Company shall have received an opinion of counsel
               satisfactory to it that an exemption from registration under such
               Act is then available, and (2) there shall have been compliance
               with all applicable state securities laws."

     b.   At the discretion of the Administrator, the Company shall have
          received an opinion of its counsel that the Shares may be issued upon
          such particular exercise or acceptance in compliance with the 1933 Act
          without registration thereunder.

22.  DISSOLUTION OR LIQUIDATION OF THE COMPANY.

     Upon the dissolution or liquidation of the Company, all Options granted
under this Plan which as of such date shall not have been exercised and all
Stock Grants which have not been accepted will terminate and become null and
void; provided, however, that if the rights of a Participant or a Participant's
Survivors have not otherwise terminated and expired, the Participant or the
Participant's Survivors will have the right immediately prior to such
dissolution or liquidation to exercise or accept any Stock Right to the extent
that the Stock Right is exercisable or subject to acceptance as of the date
immediately prior to such dissolution or liquidation.

23.  ADJUSTMENTS.

     Upon the occurrence of any of the following events, a Participant's rights
with respect to any Stock Right granted to him or her hereunder shall be
adjusted as hereinafter provided, unless otherwise specifically provided in the
pertinent Option Agreement or Stock Grant Agreement:

     A. Stock Dividends and Stock Splits. If (i) the shares of Common Stock
shall be subdivided or combined into a greater or smaller number of shares or if
the Company shall issue any shares of Common Stock as a stock dividend on its
outstanding Common Stock, or (ii) additional shares or new or different shares
or other securities of the Company or other non-cash assets are distributed with
respect to such shares of Common Stock, the number of shares of Common Stock
deliverable upon the exercise or acceptance of such Stock Right may be
appropriately increased or decreased proportionately, and appropriate
adjustments may be made in the purchase price per share to reflect such events.

     B. Consolidations or Mergers. If the Company is to be consolidated with or
acquired by another entity in a merger, sale of all or substantially all of the
Company's assets or otherwise (an "Acquisition"), the Administrator or the board
of directors of any entity assuming the obligations of the Company hereunder
(the "Successor Board"), shall, as to outstanding Options, either (i) make
appropriate provision for the continuation of such Options by substituting on an


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<PAGE>

equitable basis for the Shares then subject to such Options either the
consideration payable with respect to the outstanding shares of Common Stock in
connection with the Acquisition or securities of any successor or acquiring
entity; or (ii) upon written notice to the Participants, provide that all
Options must be exercised (either to the extent then exercisable or, at the
discretion of the Administrator, all Options being made fully exercisable for
purposes of this Subparagraph) at the end of which period the Options shall
terminate; or (iii) terminate all Options in exchange for a cash payment equal
to the excess of the Fair Market Value of the Shares subject to such Options
(either to the extent then exercisable or, at the discretion of the
Administrator, all Options being made fully exercisable for purposes of this
Subparagraph) over the exercise price thereof.

     With respect to outstanding Stock Grants, the Administrator or the
Successor Board, shall either (i) make appropriate provisions for the
continuation of such Stock Grants by substituting on an equitable basis for the
Shares then subject to such Stock Grants either the consideration payable with
respect to the outstanding Shares of Common Stock in connection with the
Acquisition or securities of any successor or acquiring entity; or (ii) upon
written notice to the Participants, provide that all Stock Grants must be
accepted (to the extent then subject to acceptance) within a specified number of
days of the date of such notice, at the end of which period the offer of the
Stock Grants shall terminate; or (iii) terminate all Stock Grants in exchange
for a cash payment equal to the excess of the Fair Market Value of the Shares
subject to such Stock Grants over the purchase price thereof, if any. In
addition, in the event of an Acquisition, the Administrator may waive any or all
Company repurchase rights with respect to outstanding Stock Grants.

     C. Recapitalization or Reorganization. In the event of a recapitalization
or reorganization of the Company (other than a transaction described in
Subparagraph B above) pursuant to which securities of the Company or of another
corporation are issued with respect to the outstanding shares of Common Stock, a
Participant upon exercising or accepting a Stock Right shall be entitled to
receive for the purchase price, if any, paid upon such exercise or acceptance
the securities which would have been received if such Stock Right had been
exercised or accepted prior to such recapitalization or reorganization.

     D. Modification of ISOs. Notwithstanding the foregoing, any adjustments
made pursuant to Subparagraph A, B or C with respect to ISOs shall be made only
after the Administrator, after consulting with counsel for the Company,
determines whether such adjustments would constitute a "modification" of such
ISOs (as that term is defined in Section 424(h) of the Code) or would cause any
adverse tax consequences for the holders of such ISOs. If the Administrator
determines that such adjustments made with respect to ISOs would constitute a
modification of such ISOs, it may refrain from making such adjustments, unless
the holder of an ISO specifically requests in writing that such adjustment be
made and such writing indicates that the holder has full knowledge of the
consequences of such "modification" on his or her income tax treatment with
respect to the ISO.


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<PAGE>

24.  ISSUANCES OF SECURITIES.

     Except as expressly provided herein, no issuance by the Company of shares
of stock of any class, or securities convertible into shares of stock of any
class, shall affect, and no adjustment by reason thereof shall be made with
respect to, the number or price of shares subject to Stock Rights. Except as
expressly provided herein, no adjustments shall be made for dividends paid in
cash or in property (including without limitation, securities) of the Company
prior to any issuance of Shares pursuant to a Stock Right.

25.  FRACTIONAL SHARES.

     No fractional shares shall be issued under the Plan and the person
exercising a Stock Right shall receive from the Company cash in lieu of such
fractional shares equal to the Fair Market Value thereof.

26.  CONVERSION OF ISOs INTO NON-QUALIFIED OPTIONS; TERMINATION OF ISOs.

     The Administrator, at the written request of any Participant, may in its
discretion take such actions as may be necessary to convert such Participant's
ISOs (or any portions thereof) that have not been exercised on the date of
conversion into Non-Qualified Options at any time prior to the expiration of
such ISOs, regardless of whether the Participant is an employee of the Company
or an Affiliate at the time of such conversion. Such actions may include, but
not be limited to, extending the exercise period or reducing the exercise price
of the appropriate installments of such Options. At the time of such conversion,
the Administrator (with the consent of the Participant) may impose such
conditions on the exercise of the resulting Non-Qualified Options as the
Administrator in its discretion may determine, provided that such conditions
shall not be inconsistent with this Plan. Nothing in the Plan shall be deemed to
give any Participant the right to have such Participant's ISOs converted into
Non-Qualified Options, and no such conversion shall occur until and unless the
Administrator takes appropriate action. The Administrator, with the consent of
the Participant, may also terminate any portion of any ISO that has not been
exercised at the time of such conversion.

27.  WITHHOLDING.

     In the event that any federal, state, or local income taxes, employment
taxes, Federal Insurance Contributions Act ("F.I.C.A.") withholdings or other
amounts are required by applicable law or governmental regulation to be withheld
from the Participant's salary, wages or other remuneration in connection with
the exercise or acceptance of a Stock Right or in connection with a
Disqualifying Disposition (as defined in Paragraph 28) or upon the lapsing of
any right of repurchase, the Company may withhold from the Participant's
compensation, if any, or may require that the Participant advance in cash to the
Company, or to any Affiliate of the Company which employs or employed the
Participant, the statutory minimum amount of such


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<PAGE>

withholdings unless a different withholding arrangement, including the use of
shares of the Company's Common Stock or a promissory note, is authorized by the
Administrator (and permitted by law). For purposes hereof, the fair market value
of the shares withheld for purposes of payroll withholding shall be determined
in the manner provided in Paragraph 1 above, as of the most recent practicable
date prior to the date of exercise. If the fair market value of the shares
withheld is less than the amount of payroll withholdings required, the
Participant may be required to advance the difference in cash to the Company or
the Affiliate employer. The Administrator in its discretion may condition the
exercise of an Option for less than the then Fair Market Value on the
Participant's payment of such additional withholding.

28.  NOTICE TO COMPANY OF DISQUALIFYING DISPOSITION.

     Each Key Employee who receives an ISO must agree to notify the Company in
writing immediately after the Key Employee makes a Disqualifying Disposition of
any shares acquired pursuant to the exercise of an ISO. A Disqualifying
Disposition is defined in Section 424(c) of the Code and includes any
disposition (including any sale or gift) of such shares before the later of (a)
two years after the date the Key Employee was granted the ISO, or (b) one year
after the date the Key Employee acquired Shares by exercising the ISO, except as
otherwise provided in Section 424(c) of the Code. If the Key Employee has died
before such stock is sold, these holding period requirements do not apply and no
Disqualifying Disposition can occur thereafter.

29.  TERMINATION OF THE PLAN.

     The Plan will terminate on March 31, 2014, the date which is ten (10) years
from the earlier of the date of its adoption by the Board of Directors and the
date of its approval by the shareholders of the Company. The Plan may be
terminated at an earlier date by vote of the shareholders or the Board of
Directors of the Company; provided, however, that any such earlier termination
shall not affect any Option Agreements or Stock Grant Agreements executed prior
to the effective date of such termination.

30.  AMENDMENT OF THE PLAN AND AGREEMENTS.

     The Plan may be amended by the shareholders of the Company. The Plan may
also be amended by the Administrator, including, without limitation, to the
extent necessary to qualify any or all outstanding Stock Rights granted under
the Plan or Stock Rights to be granted under the Plan for favorable federal
income tax treatment (including deferral of taxation upon exercise) as may be
afforded incentive stock options under Section 422 of the Code, and to the
extent necessary to qualify the shares issuable upon exercise or acceptance of
any outstanding Stock Rights granted, or Stock Rights to be granted, under the
Plan for listing on any national securities exchange or quotation in any
national automated quotation system of securities dealers. Any amendment
approved by the Administrator which the Administrator determines is of a scope
that requires shareholder approval shall be subject to obtaining such
shareholder approval. Any modification or amendment of the Plan shall not,
without the consent of a Participant, adversely


                                       19

<PAGE>

affect his or her rights under a Stock Right previously granted to him or her.
With the consent of the Participant affected, the Administrator may amend
outstanding Option Agreements and Stock Grant Agreements in a manner which may
be adverse to the Participant but which is not inconsistent with the Plan. In
the discretion of the Administrator, outstanding Option Agreements and Stock
Grant Agreements may be amended by the Administrator in a manner which is not
adverse to the Participant.

31.  EMPLOYMENT OR OTHER RELATIONSHIP.

     Nothing in this Plan or any Option Agreement or Stock Grant Agreement shall
be deemed to prevent the Company or an Affiliate from terminating the
employment, consultancy or director status of a Participant, nor to prevent a
Participant from terminating his or her own employment, consultancy or director
status or to give any Participant a right to be retained in employment or other
service by the Company or any Affiliate for any period of time.

32.  GOVERNING LAW.

     This Plan shall be construed and enforced in accordance with the law of the
State of Delaware.


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