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                                                                    Exhibit 10.1

                                                                       METAPHORE
                                                                    CONFIDENTIAL

                         METAPHORE PHARMACEUTICALS, INC.

                             1998 STOCK OPTION PLAN

                (AS AMENDED AND RESTATED EFFECTIVE MAY 14, 2004,
EFFECTIVE WITH RESPECT TO ALL BENEFITS GRANTED UNDER THE PLAN AND THE PRIOR PLAN
                 INCLUDING THOSE BENEFITS GRANTED BEFORE 2003.)

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                         METAPHORE PHARMACEUTICALS, INC.

                             1998 STOCK OPTION PLAN

                 (as amended and restated effective May 14, 2004,
      effective with respect to all Benefits granted under the Plan and the
            Prior Plan including those Benefits granted before 2003.)

                                TABLE OF CONTENTS

                                                                            PAGE
                                                                            ----
1.   NAME AND PURPOSE                                                         1
        1.1   Name                                                            1
        1.2   Purpose                                                         1

2.   DEFINITIONS OF TERMS AND RULES OF CONSTRUCTION                           1
        2.1   General Definitions                                             1
              2.1.1  Affiliate                                                1
              2.1.2  Agreement                                                1
              2.1.3  Benefit                                                  1
              2.1.4  Board                                                    1
              2.1.5  Board Advisor                                            2
              2.1.6  Business Entity                                          2
              2.1.7  Cause                                                    2
              2.1.8  Change of Control                                        2
              2.1.9  Code                                                     3
              2.1.10 Company                                                  3
              2.1.11 Committee                                                3
              2.1.12 Common Stock                                             3
              2.1.13 Director                                                 3
              2.1.14 Effective Termination Event                              3
              2.1.15 Employee                                                 3
              2.1.16 Employer                                                 3
              2.1.17 Fair Market Value                                        3
              2.1.18 ISO                                                      4
              2.1.19 NQSO                                                     4
              2.1.20 Option                                                   4
              2.1.21 Parent                                                   4
              2.1.22 Participant                                              4
              2.1.23 Plan                                                     4
              2.1.24 Prior Plan                                               4
              2.1.25 Related Entity                                           5
              2.1.26 Reload Option                                            5
              2.1.27 SAR                                                      5
              2.1.28 Scientific Advisory Board Members                        5


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                 2.1.29 Share                                                  5
                 2.1.30 Subsidiary                                             5
         2.2     Other Definitions                                             5
         2.3     Conflicts                                                     5

3.    COMMON STOCK                                                             6
         3.1     Number of Shares                                              6
         3.2     Reusage                                                       6
         3.3     Adjustments                                                   6

4.    ELIGIBILITY                                                              6
         4.1     Determined By Committee                                       6

5.    ADMINISTRATION                                                           6
         5.1     Committee                                                     6
         5.2     Authority                                                     7
         5.3     Delegation                                                    7
         5.4     Determination                                                 7

6.    AMENDMENT OF PLAN                                                        8
         6.1     Power of Board                                                8
         6.2     Limitation                                                    8

7.    TERM AND TERMINATION OF PLAN                                             8
         7.1     Term                                                          8
         7.2     Termination                                                   8

8.    MODIFICATION OF BENEFITS                                                 8
         8.1     General Right of Committee                                    8
         8.2     Restriction                                                   8

9.    CHANGE OF CONTROL                                                        9
         9.1     Committee Discretion to Protect Benefits                      9
         9.2     Automatic Accelerated Vesting of Benefits                     9

10.   AGREEMENTS                                                               9
         10.1    Grant Evidenced By Agreement                                  9
         10.2    Provisions of Agreement                                      10
         10.3    Transferability                                              10

11.   REPLACEMENT AND TANDEM AWARDS                                           10
         11.1    Replacement                                                  10
         11.2    Tandem Awards                                                10

12.   PAYMENT, DIVIDENDS, DEFERRAL AND WITHHOLDING                            10
         12.1    Payment                                                      10
         12.2    Dividend Equivalents                                         11
         12.3    Deferral                                                     11


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         12.4    Withholding                                                  11

13.   OPTIONS                                                                 11
         13.1    Types of Options                                             11
         13.2    Grant of ISOs and Option Price                               11
         13.3    Other Requirements for ISOs                                  12
         13.4    NQSOs                                                        12
         13.5    Determination by Committee                                   12

14.   SARS                                                                    12
         14.1    Grant and Payment                                            12
         14.2    Grant of Tandem Award                                        12
         13.3    ISO Tandem Award                                             12
         14.4    Payment of Awards                                            12

15.   MISCELLANEOUS PROVISIONS                                                12
         15.1    Underscored References                                       12
         15.2    Number and Gender                                            13
         15.3    Unfunded Status of Plan                                      13
         15.4    Termination of Employment                                    13
         15.5    Designation of Beneficiary                                   14
         15.6    Governing Law                                                15
         15.7    Purchase for Investment                                      15
         15.8    No Employment Contract                                       15
         15.9    No Effect on Other Benefits                                  15
         15.10   Restrictions                                                 15


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                         METAPHORE PHARMACEUTICALS, INC.

                             1998 STOCK OPTION PLAN

                (as amended and restated effective May 14, 2004,
effective with respect to all Benefits granted under the Plan and the Prior Plan
                 including those Benefits granted before 2003.)

1    NAME AND PURPOSE

     1.1  NAME.

          The name of this Plan is the "Metaphore Pharmaceuticals, Inc. 1998
Stock Option Plan."

     1.2  PURPOSE.

          The Company has established this Plan to attract, retain, motivate and
reward Employees and other individuals and to encourage ownership of the
Company's Common Stock by Employees and other individuals.

2    DEFINITIONS OF TERMS AND RULES OF CONSTRUCTION

     2.1  GENERAL DEFINITIONS.

          The following words and phrases, when used in the Plan, unless
otherwise specifically defined or unless the context clearly otherwise requires,
shall have the following respective meanings:

          2.1.1 AFFILIATE.

               A Parent or Subsidiary of the Company or any Business Entity
     which, directly or indirectly, is controlled by the Company.

          2.1.2 AGREEMENT.

               The document which evidences the grant of any Benefit under the
     Plan and which sets forth the Benefit and the terms, conditions and
     provisions of, and restrictions relating to, such Benefit.

          2.1.3 BENEFIT.

               Any benefit granted to a Participant under the Plan

          2.1.4 BOARD.

               The Board of Directors of the Company.


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          2.1.5 BOARD ADVISOR.

               An advisor of the Board, so designated by the Board.

          2.1.6 BUSINESS ENTITY.

               Any corporation, partnership, limited liability partnership,
     limited liability company, trust, association, or other business or not for
     profit entity.

          2.1.7 CAUSE.

               Cause shall be determined by the Committee and shall include, but
     not be limited to, gross negligence, willful misconduct, flagrant or
     repeated violations of the Employer's policies, rules or ethics,
     intoxication, substance abuse, sexual or other unlawful harassment,
     disclosure of confidential or proprietary information, engaging in a
     business competitive with the Employer, or dishonest, illegal or immoral
     conduct.

          2.1.8 CHANGE OF CONTROL.

               Change of Control means any of the following:

               (a) The acquisition, with or without the approval of the Board,
     by any "person" or "group" (as that term is used in Section 13(d) and
     14(d)(2) of the Securities Exchange Act of 1934, as amended ("Exchange
     Act")), other than the Company or a Related Entity, of beneficial ownership
     (as defined in Rule 13d-3 under the Exchange Act) of outstanding voting
     securities of the Company carrying more than 20% of the combined voting
     power in the election of directors through a tender offer, exchange offer
     or otherwise provided, however, that the sale of voting securities by the
     Company that constitutes a financing round shall not constitute a Change of
     Control;

               (b) the liquidation or dissolution of the Company following a
     sale or other disposition of all or substantially all of its assets;

               (c) a merger or consolidation involving the Company as a result
     of which persons who were shareholders of the Company immediately prior
     to the effective date of the merger or consolidation shall have beneficial
     ownership of less than 50% of the combined voting power in the election of
     directors of the surviving corporation following the effective date of such
     merger or consolidation;

               (d) or any time during any two year period in which individuals
     who constituted the Board at the start of such period (or whose election
     was approved by at least two thirds of the then members of the Board who
     were members at the start of the two year period) do not constitute at
     least 50% of the Board for any reason.

     In addition, in the case of Participants employed by a Subsidiary or a
     division of the Company or a Subsidiary, the sale of a Subsidiary or the
     sale of all or substantially all of the assets of the Subsidiary or
     division shall constitute a Change of Control.


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     2.1.9 CODE.

          The Internal Revenue Code of 1986, as amended. Any reference to the
Code includes the regulations promulgated pursuant to the Code.

     2.1.10 COMPANY.

          Metaphore Pharmaceuticals, Inc.

     2.1.11 COMMITTEE.

          The Committee described in Section 5.1.

     2.1.12 COMMON STOCK.

          The Company's common stock.

     2.1.13 DIRECTOR.

          A member of the Board or a member of the Board of Directors of an
Affiliate.

     2.1.14 EFFECTIVE TERMINATION EVENT.

          Any of the following events: a termination of Participant's employment
by the Employer without Cause; a material decrease in Participant's
compensation; a substantial decrease in the nature or scope of Participant's
duties, responsibilities, powers, authority, title, position or status; or a
material breach by the Employer of an employment, compensation or similar
agreement between the Participant and the Employer.

     2.1.15 EMPLOYEE.

          Any person employed by the Employer.

     2.1.16 EMPLOYER.

          The Company and all Affiliates.

     2.1.17 FAIR MARKET VALUE.

          The last sale price, regular way, or, in case no such sale takes place
on such date, the average of the closing bid and asked prices, regular way, of
the Shares, in either case as reported in the principal consolidated transaction
reporting system with respect to securities listed or admitted to trading on the
New York Stock Exchange, Inc. (the "NYSE") or, if the Shares are not listed or
admitted to trading on the NYSE, as reported in the principal consolidated
transaction reporting system with respect to securities listed on the principal
national securities exchange on which the Shares are listed or admitted to
trading or, if the Shares are not listed or admitted to trading on any


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national securities exchange, the last quoted sale price on such date or, if not
so quoted, the average of the high bid and low asked prices in the
over-the-counter market on such date, as reported by the National Association of
Securities Dealers, Inc. Automated Quotations System or such other system then
in use, or, if on any such date the Shares are not quoted by any such
organization, the average of the closing bid and asked prices on such date as
furnished by a professional market maker making a market in the Shares selected
by the Committee. If the Shares are not publicly held or so listed or publicly
traded, the determination of the Fair Market Value per Share shall be made in
good faith by the Committee.

     2.1.18 ISO.

          An Incentive Stock Option as defined in Section 422 of the Code.

     2.1.19 NQSO.

          A non-qualified stock Option, which is an Option that does not qualify
as an ISO.

     2.1.20 OPTION.

          An option to purchase Shares granted under the Plan.

     2.1.21 PARENT.

          Any Business Entity (other than the Company or a Subsidiary) in an
unbroken chain of Business Entities ending with the Company, if, at the time of
the grant of an Option or other Benefit, each of the Business Entities (other
than the Company) owns equity possessing 50% or more of the total combined
voting power of all classes of equity in one of the other Business Entities in
such chain.

     2.1.22 PARTICIPANT.

          An individual who is granted a Benefit under the Plan. Benefits may be
granted only to Employees, Directors, Board Advisors, Scientific Advisory Board
Members or consultants of the Company or an Affiliate.

     2.1.23 PLAN.

          The Metaphore Pharmaceuticals, Inc. 1998 Stock Option Plan and all
amendments and supplements to it.

     2.1.24 PRIOR PLAN.

          The MetaPhore Pharmaceuticals, Inc. 1998 Stock Option Plan as amended
up to January 1, 1999. As of January 1, 1999, the Plan shall be an amendment and
restatement of the Prior Plan.


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          2.1.25 RELATED ENTITY.

               The Parent, a Subsidiary or any employee benefit plan (including
     a trust forming a part of such a plan) maintained by the Parent, the
     Company or a Subsidiary.

          2.1.26 RELOAD OPTION.

               An Option to purchase the number of Shares used by a Participant
     to exercise an Option and to satisfy any withholding requirement incident
     to the exercise of such Option

          2.1.27 SAR.

               A stock appreciation right, which is the right to receive an
     amount equal to the appreciation, if any, in the Fair Market Value of a
     Share from the date of the grant of the right to the date of its payment

          2.1.28 SCIENTIFIC ADVISORY BOARD MEMBERS.

               An member of the scientific advisory board of the Company, so
     designated by the Board

          2.1.29 SHARE.

               A share of Common Stock

          2.1.30 SUBSIDIARY.

               Any Business Entity (other than the Company) in an unbroken chain
     of Business Entities beginning with the Company if, at the time of grant of
     an Option or other Benefit, each of the Business Entities, other than the
     last Business Entity in the unbroken chain, owns equity possessing 50% or
     more of the total combined voting power of all classes of equity in one of
     the other Business Entities in such chain.

     2.2  OTHER DEFINITIONS.

          In addition to the above definitions, certain words and phrases used
in the Plan and any Agreement may be defined in other portions of the Plan or in
such Agreement.

     2.3  CONFLICTS.

          In the case of any conflict in the terms of the Plan relating to a
Benefit, the provisions in the section of the Plan which specifically grants
such Benefit shall control those in a different section. In the case of any
conflict between the terms of the Plan relating to a Benefit and the terms of an
Agreement relating to a Benefit, the terms of the Plan shall control.


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3.   COMMON STOCK

     3.1  NUMBER OF SHARES.

          The number of Shares which may be issued or sold or for which Options
or SARs may be granted under the Plan shall be 4,308,219 Shares. Such Shares may
be authorized but unissued Shares, Shares held in the treasury, or both The full
number of Shares available may be used for any type of Option or SAR

     3.2  REUSAGE.

          If an Option or SAR expires or is terminated, surrendered, or canceled
without having been fully exercised, the Shares covered by such Option or SAR,
as the case may be, shall again be available for use under the Plan. Any Shares
which are used as full or partial payment to the Company upon exercise of an
Option shall be available for purposes of the Plan

     3.3  ADJUSTMENTS.

          If there is any change in the Common Stock of the Company by reason of
any stock split, stock dividend, spin off, split up, spin out, recapitalization,
merger, consolidation, reorganization, combination or exchange of shares, or
otherwise, the number of SARs and number and class of shares available for
Options and the number of Shares subject to outstanding Options or SARs, and the
price thereof, as applicable, shall be appropriately adjusted by the Committee.

4.   ELIGIBILITY

     4.1  DETERMINED BY COMMITTEE.

          The Participants and the Benefits they receive under the Plan shall be
determined solely by the Committee. In making its determinations, the Committee
shall consider past, present and expected future contributions of Participants
and potential Participants to the Employer, including, without limitation, the
performance of, or the refraining from the performance of, services. Unless
specifically provided otherwise herein, all determinations of the Committee in
connection with the Plan or an Agreement shall be made in its sole discretion

5.   ADMINISTRATION

     5.1  COMMITTEE.

          The Plan shall be administered by the Committee. The Committee shall
consist of the Board, unless the Board appoints a Committee of three or more but
less than all of the Board. If the Committee does not include the entire Board,
it shall serve at the pleasure of the Board, which may from time to time appoint
members in substitution for members previously appointed and fill vacancies,
however caused, in the Committee. The Committee may select one of its members as
its Chairman and shall hold its meetings at such times and places as it may
determine. A majority of its members shall constitute a quorum. All
determinations of the Committee made at a meeting at which a quorum is present
shall be made by a majority of its


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members present at the meeting. Any decision or determination reduced to writing
and signed by a majority of the members shall be fully as effective as if it had
been made by a majority vote at a meeting duly called and held.

     5.2  AUTHORITY.

          Subject to the terms of the Plan, the Committee shall have
discretionary authority to:

          (a) determine the individuals to whom Benefits are granted, the type
     and amounts of Benefits to be granted and the date of issuance and duration
     of all such grants;

          (b) determine the terms, conditions and provisions of, and
     restrictions relating to, each Benefit granted;

          (c) interpret and construe the Plan and all Agreements;

          (d) prescribe, amend and rescind rules and regulations relating to the
     Plan;

          (e) determine the content and form of all Agreements;

          (f) determine all questions relating to Benefits under the Plan;

          (g) maintain accounts, records and ledgers relating to Benefits;

          (h) maintain records concerning its decisions and proceedings;

          (i) employ agents, attorneys, accountants or other persons for such
     purposes as the Committee considers necessary or desirable;

          (j) take, at any time, any action required or permitted by Section 9
     irrespective of whether any Change of Control has occurred or is imminent;

          (k) determine limits on Options and SARs which may be granted to any
     Participant over a particular period of time; and

          (l) do and perform all acts which it may deem necessary or appropriate
     for the administration of the Plan and carry out the purposes of the Plan.

     5.3  DELEGATION.

          The Committee may delegate all or any part of its authority under the
Plan to any Employee, Employees or committee.

     5.4  DETERMINATION.

          All determinations of the Committee shall be final.


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6.   AMENDMENT OF PLAN.

     6.1  POWER OF BOARD.

          Except as provided in Section 6.2 or 8.2, the Board shall have the
sole right and power to amend the Plan at any time and from time to time.

     6.2  LIMITATION.

          The Board may not amend the Plan, without approval of the shareholders
of the Company:

          (a) in a manner which would cause Options which are intended to
     qualify as ISOs to fail to qualify; or

          (b) in a manner which would violate applicable law.

7.   TERM AND TERMINATION OF PLAN

     7.1  TERM.

          The Plan shall commence as of January 1, 1999 and, subject to the
terms of the Plan, including those requiring approval by the shareholders of the
Company and those limiting the period over which ISOs or any other Benefits may
be granted, shall continue in full force and effect until terminated.

     7.2  TERMINATION.

          Subject to Section 8.2, the Plan may be terminated at any time by the
Board.

8.   MODIFICATION OF BENEFITS

     8.1  GENERAL RIGHT OF COMMITTEE.

          Subject to Section 8.2, any Benefit may be converted, modified,
forfeited or canceled, in whole or in part, by the Committee if and to the
extent permitted in the Plan or applicable Agreement. Except as may be provided
in an Agreement, the Committee may, in its sole discretion, in whole or in part,
waive any restrictions or conditions applicable to, or accelerate the vesting
of, any Benefit.

     8.2  RESTRICTION.

          Notwithstanding the provisions of Sections 6.1, 7.2 or 8.1, without
the consent of the Participant to whom a Benefit was granted, no amendment or
termination of the Plan or conversion, modification, forfeiture or cancellation
of a Benefit may adversely affect such Participant's right to such Benefit
granted prior to such amendment or termination of the Plan or conversion,
modification, forfeiture or cancellation of such Benefit.


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9    CHANGE OF CONTROL

     9.1  COMMITTEE DISCRETION TO PROTECT BENEFITS.

          In order to maintain a Participant's rights in the event of a Change
of Control, the Committee, in its sole discretion, may, in any Agreement
evidencing a Benefit, or at any time prior to, or simultaneously with or after a
Change in Control, provide such protection as it may deem necessary. Without in
any way limiting the generality of the foregoing sentence or requiring any
specific protection, the Committee may:

          (a) provide for the acceleration of any time periods relating to the
     exercise or realization of such benefit so that such benefit may be
     exercised or realized on or before a date fixed by the Committee;

          (b) provide for the purchase of any Benefit for an amount of cash
     equal to the amount which could have been attained upon the exercise or
     realization of such Benefit had such Benefit been currently exercisable or
     payable;

          (c) make such adjustment to the Benefits then outstanding as the
     Committee deems appropriate to reflect such transaction or change; and/or

          (d) cause the Benefits then outstanding to be assumed, or new Benefits
     substituted therefor, by the surviving corporation in such change.

     9.2  AUTOMATIC ACCELERATED VESTING OF BENEFITS.

          Without the necessity of any action by the Committee, if within the
one (1) year period following a Change of Control, a Participant experiences an
Effective Termination Event, then effective upon the Company's receipt from
Participant of written notice of such Effective Termination Event, then all time
periods relating to the exercise or realization of the Participant's Benefit
shall be accelerated so that such Benefit may be exercised or realized in
accordance with the Participant's Agreement as if fully vested on the
termination date and as if the Participant was terminated without Cause.
Participant's written notice shall be sent to the Company's corporate offices
and shall set forth in reasonable detail (a) the facts and circumstances claimed
to provide a basis for Effective Termination Event, and (b) if the termination
date is other than the date of receipt of such notice, the actual termination
date.

10.  AGREEMENTS

     10.1 GRANT EVIDENCED BY AGREEMENT.

          The grant of any Benefit under the Plan may be evidenced by an
Agreement which shall describe the specific Benefit granted and the terms and
conditions of the Benefit. The granting of any Benefit shall be subject to, and
conditioned upon, the recipient's execution of any Agreement required by the
Committee. Except as otherwise provided in an Agreement, all capitalized terms
used in the Agreement shall have the same meaning as in the Plan, and the
Agreement shall be subject to all of the terms of the Plan.


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     10.2 PROVISIONS OF AGREEMENT.

          Each Agreement shall contain such provisions that the Committee shall
determine to be necessary, desirable and appropriate for the Benefit granted
which may include, but not necessarily be limited to, the following with respect
to any Benefit: description of the type of Benefit; the Benefit's duration; its
transferability; if an Option, the exercise price, the exercise period and the
person or persons who may exercise the Option; the effect upon such Benefit of
the Participant's death, disability, changes of duties or termination of
employment; the Benefit's conditions; when, if, and how any Benefit may be
forfeited, converted into another Benefit, modified, exchanged for another
Benefit, or replaced; and the restrictions on any Shares purchased or granted
under the Plan.

     10.3 TRANSFERABILITY.

          Unless otherwise specified in an Agreement or permitted by the
Committee, each Benefit granted shall be not transferable other than by will or
the laws of descent and distribution and shall be exercisable during a
Participant's lifetime only by him.

11.  REPLACEMENT AND TANDEM AWARDS

     11.1 REPLACEMENT.

          The Committee may permit a Participant to elect to surrender a Benefit
in exchange for a new Benefit.

     11.2 TANDEM AWARDS.

          Awards may be granted by the Committee in tandem. However, no Benefit
may be granted in tandem with an ISO except SARs.

12.  PAYMENT, DIVIDENDS, DEFERRAL AND WITHHOLDING

     12.1 PAYMENT.

          Upon the exercise of an Option, the amount due the Company is to be
paid:

          (a) in cash;

          (b) by the surrender of all or part of a Benefit (including the Option
     being exercised);

          (c) by the tender to the Company of Shares owned by the Participant
     and registered in his name having a Fair Market Value equal to the amount
     due to the Company;

          (d) in other property, rights and credits deemed acceptable by the
     Committee, including the Participant's promissory note;

          (e) by a cashless exercise arrangement or an attestation arrangement;
     or


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          (f) by any combination of the payment methods specified in (a), (b),
     (c), (d), and (e) above

          Notwithstanding, the foregoing, any method of payment other than (a)
may be used only with the consent of the Committee or if and to the extent so
provided in an Agreement. The proceeds of the sale of Shares purchased pursuant
to an Option and any payment to the Company for other Benefits shall be added to
the general funds of the Company or to the Shares held in treasury, as the case
may be, and used for the corporate purposes of the Company as the Board shall
determine.

     12.2 DIVIDEND EQUIVALENTS.

          Grants of Benefits in Shares or Share equivalents may include dividend
equivalent payments or dividend credit rights.

     12.3 DEFERRAL.

          The right to receive any Benefit under the Plan may, at the request
of the Participant, be deferred for such period and upon such terms as the
Committee shall determine, which may include crediting of interest on deferrals
of cash and crediting of dividends on deferrals denominated in Shares.

     12.4 WITHHOLDING.

          The Company may, at the time any distribution is made under the Plan,
whether in cash or in Shares, or at the time any Option is exercised, withhold
from such distribution or Shares issuable upon the exercise of an Option, any
amount necessary to satisfy federal, state and local income and/or other tax
withholding requirements with respect to such distribution or exercise of such
Options. The Committee or the Company may require a participant to tender to the
Company cash and/or Shares in the amount necessary to comply with any such
withholding requirements.

13.  OPTIONS.

     13.1 TYPES OF OPTIONS.

          It is intended that both ISOs and NQSOs, which may be Reload Options,
may be granted by the Committee under the Plan.

     13.2 GRANT OF ISOS AND OPTION PRICE.

          Each ISO must be granted to an Employee and granted within ten years
from January 21, 1998, which is the date which is earlier of the date of
adoption of the Prior Plan by the Board or Company's shareholders. The purchase
price for Shares under any ISO shall be no less than the Fair Market Value of
the Shares at the time the Option is granted.


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     13.3 OTHER REQUIREMENTS FOR ISOS.

          The terms of each Option which is intended to qualify as an ISO shall
meet all requirements of Section 422 of the Code.

     13.4 NQSOs.

          The terms of each NQSO shall provide that such Option will not be
treated as an ISO. The purchase price for Shares under any NQSO shall be no less
than $.01 per Share.

     13.5 DETERMINATION BY COMMITTEE.

          Except as otherwise provided in Section 13.2 through Section 13.4,
the terms of all Options shall be determined by the Committee.

14.  SARS.

     14.1 GRANT AND PAYMENT.

          The Committee may grant SARs. Upon electing to receive payment of a
SAR, a Participant shall receive payment in cash, in Shares, or in any
combination of cash and Shares, as the Committee shall determine.

     14.2 GRANT OF TANDEM AWARD.

          The Committee may grant SARs in tandem with an Option, in which case:
the exercise of the Option shall cause a correlative reduction in SARs standing
to a Participant's credit which were granted in tandem with the Option; and the
payment of SARs shall cause a correlative reduction of the Shares under such
Option.

     14.3 ISO TANDEM AWARD.

          When SARs are granted in tandem with an ISO, the SARs shall have such
terms and conditions as shall be required for the ISO to qualify as an ISO.

     14.4 PAYMENT OF AWARD.

          SARs shall be paid by the Company to a Participant, to the extent
payment is elected by the Participant (and is otherwise due and payable), as
soon as practicable after the date on which such election is made.

15.  MISCELLANEOUS PROVISIONS

     15.1 UNDERSCORED REFERENCES.

          The underscored references contained in the Plan are included only for
convenience, and they shall not be construed as a part of the Plan or in any
respect affecting or modifying its provisions.


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     15.2 NUMBER AND GENDER.

          The masculine and neuter, wherever used in the Plan, shall refer to
either the masculine, neuter or feminine; and, unless the context otherwise
requires, the singular shall include the plural and the plural the singular.

     15.3 UNFUNDED STATUS OF PLAN.

          The Plan is intended to constitute an "unfunded" plan for incentive
and deferred compensation. With respect to any payments or deliveries of Shares
not yet made to a Participant by the Company, nothing contained herein shall
give any rights that are greater than those of a general creditor of the
Company. The Committee may authorize the creation of trusts or other
arrangements to meet the obligations created under the Plan to deliver Shares or
payments hereunder consistent with the foregoing.

     15.4 TERMINATION OF EMPLOYMENT.

               (a) If the employment of a Participant by the Company terminates
     for any reason, except as otherwise provided in an Agreement, all
     unexercised, deferred, and unpaid Benefits may be exercisable or paid only
     in accordance with rules established by the Committee. These rules may
     provide, as the Committee may deem appropriate, for the expiration,
     forfeiture, continuation, or acceleration of the vesting of all or part of
     the Benefits.

               (b) For all awards of Benefits prior to January 1, 2002 and for
     all awards of Benefits on or after January 1, 2002 which do not
     specifically override this Section 15.4(b) in the Award, the following
     shall apply in the event of termination of employment:

                    (i) Termination for Cause After Option is Vested. If, on or
     after the date that the Option shall have first become exercisable, the
     Participant's employment shall be terminated by the Employer for. "Cause",
     as defined below, then the Participant's full interest in the Option shall
     terminate on the date of such termination of employment and all rights
     thereunder shall cease. Whether a Participant's employment is terminated
     for Cause shall be determined by the Committee. Cause shall include, but
     not be limited to gross negligence, willful misconduct, flagrant or
     repeated violations of the Employer's policies, rules or ethics,
     intoxication, substance abuse, sexual or other unlawful harassment,
     disclosure of confidential or proprietary information, engaging in a
     business competitive with the Employer, or dishonest, illegal or immoral
     conduct. The employment of a Director, Board Advisor or Scientific Advisory
     Board Member shall be deemed to be terminated when he ceases to be in such
     role. If a Participant is both a Director, Board Advisor or Scientific
     Advisory Board Member and an Employee, his employment shall not be deemed
     to have been terminated as long as he remains in any of those roles.

                    (ii) Other Termination After Option is Vested If, on or
     after the date that the Option shall first have become exercisable, the
     Participant's employment shall be terminated for disability (as such term
     is defined at Section 422(c)(6) of the


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     Code), for death, by the Employer without Cause, or by the Participant,
     then the Participant or his personal representative and/or beneficiary, as
     the case may be, shall have the right (but not later than the Option
     Expiration Date) to exercise such Option to the extent that such Option or
     any installment thereof shall have accrued at the date of such termination
     of employment and shall not have been exercised (A) for one year following
     termination of employment, if the Participant becomes disabled or dies, and
     (B) for three months following termination of employment, in the other
     cases described in this Section 15.4(b)(ii). If the Participant's
     employment terminates for a reason described in this Section 15.4(b)(ii)
     other than death or disability, and, if the Participant dies or becomes
     disabled prior to three months following termination of employment, then
     the Participant or his personal representative and/or beneficiary, as the
     case may be, shall have the right (but not later than the Option Expiration
     Date), to exercise such Option to the extent that such Option or any
     installment thereof shall have accrued at the date of such termination of
     employment and shall not have been exercised for a period which, when added
     to the period which has elapsed following termination of employment until
     death or disability, equals one year Notwithstanding the foregoing, if the
     employment of a Director or a Scientific Advisory Board Member is
     terminated for a reason described in this Section 15.4(b)(ii), the Director
     or Scientific Advisory Board Member, or his personal representative and/or
     beneficiary, as the case may be, shall have the right to exercise any
     Option granted on or after July 23, 2004 to the extent that such Option or
     any installment thereof shall have accrued at the date of such termination
     of employment and shall not have been exercised, until the first
     anniversary of the date of such termination of employment. The employment
     of a Director, Board Advisor or Scientific Advisory Board Member shall be
     deemed to have been terminated by the Employer without Cause if the
     Participant ceases to serve in such role solely due to the failure to be
     reelected or reappointed and such failure is not a result of an act or
     omission which would constitute Cause.

                    (iii) Option Not Vested If the Participant's employment (or
     service as a Director, Board Advisor or Scientific Advisory Board Member)
     shall terminate before all or part of the Option shall have first become
     exercisable, then the Participant's interest in the Option to the extent
     not vested shall terminate and all rights to the extent not vested shall
     cease.

     15.5 DESIGNATION OF BENEFICIARY.

          A Participant may file with the Committee a written designation of a
beneficiary or beneficiaries (subject to such limitations as to the classes and
number of beneficiaries and contingent beneficiaries as the Committee may from
time to time prescribe) to exercise, in the event of the death of the
Participant, an Option, or to receive, in such event, any Benefits. The
Committee reserves the right to review and approve beneficiary designations. A
Participant may from time to time revoke or change any such designation of
beneficiary and any designation of beneficiary under the Plan shall be
controlling over any other disposition, testamentary or otherwise; provided,
however, that if the Committee shall be in doubt as to the right of any such
beneficiary to exercise any Option or to receive any Benefit, the Committee may
determine to recognize only an exercise by the legal representative of the
recipient, in which case the


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Company, the Committee and the members thereof shall not be under any further
liability to anyone.

     15.6 GOVERNING LAW.

          This Plan shall be construed and administered in accordance with the
laws of the State of Missouri.

     15.7 PURCHASE FOR INVESTMENT.

          So long as the Common Stock of the Company is not publicly traded, the
Committee may require each person purchasing Shares pursuant to an Option or
other award under the Plan to represent to and agree with the Company in writing
that such person is acquiring the Shares for investment and without a view to
distribution or resale. The certificates for such Shares may include any legend
which the Committee deems appropriate to reflect any restrictions on transfer.
All certificates for Shares delivered under the Plan shall be subject to such
stock transfer orders and other restrictions as the Committee may deem advisable
under all applicable laws, rules and regulations, and the Committee may cause a
legend or legends to be put on any such certificates to make appropriate
references to such restrictions.

     15.8 NO EMPLOYMENT CONTRACT.

          Neither the adoption of the Plan nor any Benefit granted hereunder
shall confer upon any Employee any right to continued employment nor shall the
Plan or any Benefit interfere in any way with the right of the Employer to
terminate the employment of any of its Employees at any time.

     15.9 NO EFFECT ON OTHER BENEFITS.

          The receipt of Benefits under the Plan shall have no effect on any
benefits to which a Participant may be entitled from the Employer, under another
plan or otherwise, or preclude a Participant from receiving any such benefits.

     15.10 RESTRICTIONS.

          In addition to any restrictions imposed upon Shares acquired under the
Plan set forth in Section 15.7, such Shares shall be subject to any restrictions
contained in the Agreement or in any other agreement between the Participant and
the Employer.


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