<PAGE>


EXHIBIT 10.33       VION PHARMACEUTICALS, INC. AMENDED AND
                  RESTATED 1993 STOCK OPTION PLAN, AS AMENDED

         1. PURPOSE. The purpose of this plan (the "Plan") is to secure for Vion
Pharmaceuticals, Inc. (the "Corporation") and its stockholders the benefits
arising from capital stock ownership by employees, officers and directors of,
and consultants or advisors to, the Corporation and its subsidiary corporations
who are expected to contribute to the Corporation's future growth and success.
Except where the context otherwise requires, the term "Corporation" shall
include all present and future subsidiaries of the Corporation as defined in
Sections 424(e) and 424(f) of the Internal Revenue Code of 1986, as amended or
replaced from time to time (the "Code"). Those provisions of the Plan which make
express reference to Section 422 shall apply only to Incentive Stock Options (as
that term is defined in the Plan).

         2. TYPE OF OPTIONS AND ADMINISTRATION.

(a)       Types of Options. Options granted pursuant to the Plan shall be
authorized by action of the Board of Directors of the Corporation (or a
Committee designated by the Board of Directors) and may be either incentive
stock options ("Incentive Stock Options") meeting the requirements of Section
422 of the Code or non-statutory options which are not intended to meet the
requirements of Section 422 of the Code.

(b)       Administration. The Plan will be administered by the Board of
Directors of the Corporation, whose construction and interpretation of the terms
and provisions of the Plan shall be final and conclusive. The Board of Directors
may in its sole discretion grant options to purchase shares of the Corporation's
Common Stock, $.01 par value per share ("Common Stock") and issue shares upon
exercise of such options as provided in the Plan. The Board shall have
authority, subject to the express provisions of the Plan, to construe the
respective option agreements and the Plan, to prescribe, amend and rescind rules
and regulations relating to the Plan, to determine the terms and provisions of
the respective option agreements, which need not be identical, and to make all
other determinations in the judgment of the Board of Directors necessary or
desirable for the administration of the Plan. The Board of Directors may correct
any defect or supply any omission or reconcile any inconsistency in the Plan or
in any option agreement in the manner and to the extent it shall deem expedient
to carry the Plan into effect and it shall be the sole and final judge of such
expediency. No director or person acting pursuant to authority delegated by the
Board of Directors shall be liable for any action or determination under the
Plan made in good faith. The Board of Directors may, to the full extent
permitted by or consistent with applicable laws or regulations (including,
without limitation, applicable state law and Rule 16b-3 promulgated under the
Securities Exchange Act of 1934 (the "Exchange Act"), or any successor rule
("Rule 16b-3")), delegate any or all of its powers under the Plan to a committee
(the "Committee") appointed by the Board of Directors, and if the Committee is
so appointed all references to the Board of Directors in the Plan shall mean and
relate to such Committee with respect to the powers so delegated.

(c)       Applicability of Rule 16b-3. Those provisions of the Plan which make
express reference to Rule 16b-3 shall apply to the Corporation only at such time
as the





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Corporation's Common Stock is registered under the Exchange Act, subject
to the last sentence of Section 3(b), and then only to such persons as are
required to file reports under Section 16(a) of the Exchange Act (a "Reporting
Person").

         3. ELIGIBILITY.

(a)      General. Options may be granted to persons who are, at the time of
grant, employees, officers or directors of, or consultants or advisors to, the
Corporation; provided, that Incentive Stock Options may only be granted to
individuals who are employees of the Corporation (within the meaning of Section
3401(c) of the Code). A person who has been granted an option may, if he or she
is otherwise eligible, be granted additional options if the Board of Directors
shall so determine.

(b)       Grant of Options to Reporting Persons. From and after the registration
of the Common Stock of the Corporation under the Exchange Act, the selection of
a director or an officer who is a Reporting Person (as the terms "director" and
"officer" are defined for purposes of Rule 16b-3) as a recipient of an option,
the timing of the option grant, the exercise price of the option and the number
of shares subject to the option shall be determined either (i) by the Board of
Directors, of which all members shall be "disinterested persons" (as hereinafter
defined), or (ii) by a committee consisting of two or more directors having full
authority to act in the matter, each of whom shall be a "disinterested person."
For the purposes of the Plan, a director shall be deemed to be a "disinterested
person" only if such person qualifies as a "disinterested person" within the
meaning of Rule 16b-3, as such term is interpreted from time to time. If at
least two of the members of the Board of Directors do not qualify as a
"disinterested person" within the meaning of Rule 16b-3, as such term is
interpreted from time to time, then the granting of options to officers and
directors who are Reporting Persons under the Plan shall not be determined in
accordance with this Section 3(b) but shall be determined in accordance with the
other provisions of the Plan.

(c)       Directors' Options. Directors of the Company who are not employees or
beneficial owners of 5% or more of the outstanding Common Stock of the Company
("Eligible Directors") and who are elected to the Board of Directors subsequent
to the date hereof will be granted an option ("Director Option") to purchase
20,000 shares of Common Stock on the date that such person is first elected or
appointed a director (an "Initial Director Option"). Each Eligible Director
other than the Chairman of the Board will receive an automatic grant of a
Director Option to purchase 15,000 shares of Common Stock on the day immediately
following the date of each annual meeting of stockholders held subsequent to
December 31, 1998, as long as such director is a member of the Board of
Directors, and provided that such director did not receive an Initial Director
Option since the previous annual meeting of stockholders. The Chairman of the
Board, if an Eligible Director, will receive an automatic grant of a Director
Option to purchase 20,000 shares of Common Stock on the day immediately
following the date of each annual meeting of stockholders held subsequent to
December 31, 1998, as long as such director is a member of the Board of
Directors, and provided that such director did not receive an Initial Director
Option since the previous annual meeting of stockholders. The exercise price for
each share subject to a Director Option shall be equal to the fair market value
of the Common Stock on the date of grant. Director Options shall become
exercisable in two equal annual installments commencing one year from the date
the




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option is granted and will expire the earlier of 10 years after the date of
grant or 90 days after the termination of the director's service on the Board.
This Section 3(c) shall not be amended more than once every six months, other
than to comport with changes in the Internal Revenue Code, the Employee
Retirement Income Security Act, or the rules thereunder.

         4. STOCK SUBJECT TO PLAN. The stock subject to options granted under
the Plan shall be shares of authorized but unissued or reacquired Common Stock.
Subject to adjustment as provided in Section 15 below, the maximum number of
shares of Common Stock of the Corporation which may be issued and sold under the
Plan is 4,285,000 shares. If an option granted under the Plan shall expire,
terminate or is cancelled for any reason without having been exercised in full,
the unpurchased shares subject to such option shall again be available for
subsequent option grants under the Plan.

         5. FORMS OF OPTION AGREEMENTS. As a condition to the grant of an option
under the Plan, each recipient of an option shall execute an option agreement in
such form not inconsistent with the Plan as may be approved by the Board of
Directors. Such option agreements may differ among recipients.

         6. PURCHASE PRICE.

(a)       General. The purchase price per share of stock deliverable upon the
exercise of an option shall be determined by the Board of Directors at the time
of grant of such option; provided, however, that in the case of an Incentive
Stock Option, the exercise price shall not be less than 100% of the Fair Market
Value (as hereinafter defined) of such stock, at the time of grant of such
option, or less than 110% of such Fair Market Value in the case of options
described in Section 11(b). "Fair Market Value" of a share of Common Stock of
the Corporation as of a specified date for the purposes of the Plan shall mean
the closing price of a share of the Common Stock on the principal securities
exchange on which such shares are traded on the day immediately preceding the
date as of which Fair Market Value is being determined, or on the next preceding
date on which such shares are traded if no shares were traded on such
immediately preceding day, or if the shares are not traded on a securities
exchange, Fair Market Value shall be deemed to be the average of the high bid
and low asked prices of the shares in the over-the-counter market on the day
immediately preceding the date as of which Fair Market Value is being determined
or on the next preceding date on which such high bid and low asked prices were
recorded. If the shares are not publicly traded, Fair Market Value of a share of
Common Stock (including in the case of any repurchase of shares, any
distributions with respect thereto which would be repurchased with the shares)
shall be determined in good faith by the Board of Directors. In no case shall
Fair Market Value be determined with regard to restrictions other than
restrictions which, by their terms, will never lapse.

(b)       Payment of Purchase Price. Options granted under the Plan may provide
for the payment of the exercise price by delivery of cash or a check to the
order of the Corporation in an amount equal to the exercise price of such
options, or, to the extent provided in the applicable option agreement, (i) by
delivery to the Corporation of shares of Common Stock of the Corporation having
a Fair Market Value on the date of exercise equal in amount to the exercise
price of the options being exercised, (ii) by any other means (including,
without limitation, by delivery of a promissory note of the




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<PAGE>

optionee payable on such terms as are specified by the Board of Directors) which
the Board of Directors determines are consistent with the purpose of the Plan
and with applicable laws and regulations (including, without limitation, the
provisions of Rule 16b-3 and Regulation T promulgated by the Federal Reserve
Board) or (iii) by any combination of such methods of payment.

         7. OPTION PERIOD. Subject to earlier termination as provided in the
Plan, each option and all rights thereunder shall expire on such date as
determined by the Board of Directors and set forth in the applicable option
agreement, provided, that such date shall not be later than (10) ten years after
the date on which the option is granted.

         8. EXERCISE OF OPTIONS. Each option granted under the Plan shall be
exercisable either in full or in installments at such time or times and during
such period as shall be set forth in the option agreement evidencing such
option, subject to the provisions of the Plan. No option granted to a Reporting
Person for purposes of the Exchange Act, however, shall be exercisable during
the first six months after the date of grant. Subject to the requirements in the
immediately preceding sentence, if an option is not at the time of grant
immediately exercisable, the Board of Directors may (i) in the agreement
evidencing such option, provide for the acceleration of the exercise date or
dates of the subject option upon the occurrence of specified events, and/or (ii)
at any time prior to the complete termination of an option, accelerate the
exercise date or dates of such option.

         9. NONTRANSFERABILITY OF OPTIONS. No option granted under this Plan
shall be assignable or otherwise transferable except by the optionee (i) by will
or by the laws of descent and distribution, (ii) pursuant to a qualified
domestic relations order as defined in the Code or Title I of the Employee
Retirement Income Security Act, or the rules thereunder or (iii) as a gift to a
"Family Member" (as defined below). For purposes of this Plan, "Family Member"
means any child, stepchild, grandchild, parent, stepparent, grandparent, spouse,
former spouse, sibling, niece, nephew, mother-in-law, father-in-law, son-in-law,
daughter-in-law, brother-in-law, or sister-in-law, including adoptive
relationships, any person sharing the employee's household (other than a tenant
or employee), a trust in which these persons have more than fifty percent of the
beneficial interest, a foundation in which these persons (or the employee)
control the management of the assets, and any other entity in which these
persons (or the employee) own more than fifty percent of the voting interests.
An option may be exercised during the lifetime of the optionee only by the
optionee or by a permitted transferee as set forth in this Section 9. In the
event an optionee dies during his employment by the corporation or any of its
subsidiaries, or during the three-month period following the date of termination
of such employment, his option shall thereafter be exercisable, during the
period specified to the full extent to which such option was exercisable by the
optionee at the time of his death during the periods set forth in Section 10 or
11(d). If any optionee or permitted transferee should attempt to dispose of or
encumber his options, other than in accordance with the applicable terms of this
Plan or the applicable option agreement, his interest in such options shall
terminate.

         10. EFFECT OF TERMINATION OF EMPLOYMENT OR OTHER RELATIONSHIP. Except
as provided in Section 11(d) with respect to Incentive Stock Options, and
subject to the provisions of the Plan, an optionee or permitted transferee



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<PAGE>

may exercise an option (but only to the extent such option was exercisable at
the time of termination of the optionee's employment or other relationship with
the Corporation) at any time within three (3) months following the termination
of the optionee's employment or other relationship with the Corporation or
within one (1) year if such termination was due to the death or disability of
the optionee, but, except in the case of the optionee's death, in no event later
than the expiration date of the Option. If the termination of the optionee's
employment is for cause or is otherwise attributable to a breach by the optionee
of an employment or confidentiality or non-disclosure agreement, the option
shall expire immediately upon such termination. The Board of Directors shall
have the power to determine what constitutes a termination for cause or a breach
of an employment or confidentiality or non-disclosure agreement, whether an
optionee has been terminated for cause or has breached such an agreement, and
the date upon which such termination for cause or breach occurs. Any such
determinations shall be final and conclusive and binding upon the optionee.

         11. INCENTIVE STOCK OPTIONS. Options granted under the Plan which are
intended to be Incentive Stock Options shall be subject to the following
additional terms and conditions:

a)       Express Designation. All Incentive Stock Options granted under the
Plan shall, at the time of grant, be specifically designated as such in the
option agreement covering such Incentive Stock Options.

(b)       10% Stockholder. If any employee to whom an Incentive Stock Option is
to be granted under the Plan is, at the time of the grant of such F option, the
owner of stock possessing more than 10% of the total combined voting power of
all classes of stock of the Corporation (after taking into account the
attribution of stock ownership rules of Section 424(d) of the Code), then the
following special provisions shall be applicable to the Incentive Stock Option
granted to such individual: (i) The purchase price per share of the Common Stock
subject to such Incentive Stock Option shall not be less than 110% of the Fair
Market Value of one share of Common Stock at the time of grant; and (ii) the
option exercise period shall not exceed five years from the date of grant.

(c)       Dollar Limitation. For so long as the Code shall so provide, options
granted to any employee under the Plan (and any other incentive stock option
plans of the Corporation) which are intended to constitute Incentive Stock
Options shall not constitute Incentive Stock Options to the extent that such
options, in the aggregate, become exercisable for the first time in any one
calendar year for shares of Common Stock with an aggregate Fair Market Value, as
of the respective date or dates of grant, of more than $100,000.

(d)       Termination of Employment, Death or Disability. No Incentive Stock
Option may be exercised unless, at the time of such exercise, the optionee is,
and has been continuously since the date of grant of his or her option, employed
by the Corporation, except that: (i) an Incentive Stock Option may be exercised
within the period of three months after the date the optionee ceases to be an
employee of the Corporation (or within such lesser period as may be specified in
the applicable option agreement), provided, that the agreement with respect to
such option may designate a longer exercise period and that the exercise after
such three-month period shall be treated




                                       5






<PAGE>

as the exercise of a non-statutory option under the Plan; (ii) if the optionee
dies while in the employ of the Corporation, or within three months after the
optionee ceases to be such an employee, the Incentive Stock Option may be
exercised by the person to whom it is transferred by will or the laws of descent
and distribution within the period of one year after the date of death (or
within such lesser period as may be specified in the applicable option
agreement); and (iii) if the optionee becomes disabled (within the meaning of
Section 22(e)(3) of the Code or any successor provisions thereto) while in the
employ of the Corporation, the Incentive Stock Option may be exercised within
the period of one year after the date the optionee ceases to be such an employee
because of such disability (or within such lesser period as may be specified in
the applicable option agreement). For all purposes of the Plan and any option
granted hereunder, "employment" shall be defined in accordance with the
provisions of Section 1.421-7(h) of the Incoming Tax Regulations (or any
successor regulations). Notwithstanding the foregoing provisions to Incentive
Stock Option may be exercised after its expiration date.

         12. ADDITIONAL PROVISIONS.

(a)       Additional Option Provisions. The Board of Directors may, in its sole
discretion, include additional provisions in option agreements covering options
granted under the Plan, including without limitation restrictions on transfer,
repurchase rights, rights of first refusal, commitments to pay cash bonuses, to
make, arrange for or guaranty loans or to transfer other property to optionees
upon exercise of options, or such other provisions as shall be determined by the
Board of Directors; provided, that such additional provisions shall not be
inconsistent with any other term or condition of the Plan and such additional
provisions shall not cause any Incentive Stock Option granted under the Plan to
fail to qualify as an Incentive Stock Option within the meaning of Section 422
of the Code.

(b)       Acceleration, Extension, Etc. The Board of Directors may, in its sole
discretion, (i) accelerate the date or dates on which all or any particular
option or options granted under the Plan may be exercised or (ii) extend the
dates during which all, or any particular, option or options granted under the
Plan may be permitted if it would cause the Plan to fail to comply with Section
422 of the Code or with Rule 16b-3 (if applicable).

         13. GENERAL RESTRICTIONS.

(a)       Investment Representations. The Corporation may require any person to
whom an option is granted, as a condition of exercising such option, to give
written assurances in substance and form satisfactory to the Corporation to the
effect that such person is acquiring the Common Stock subject to the option for
his or her own account for investment and not with any present intention of
selling or otherwise distributing the same, and to such other effects as the
Corporation deems necessary or appropriate in order to comply with federal and
applicable state securities laws, or with covenants or representations made by
the Corporation in connection with any public offering of its Common Stock.

(b)       Compliance with Securities Law. Each option shall be subject to the
requirement that if, at any time, counsel to the Corporation shall determine
that the listing, registration or qualification of the shares subject to such
option upon any




                                       6





<PAGE>

securities exchange or under any state or federal law, or the consent or
approval of any governmental or regulatory body, or that the disclosure of
non-public information or the satisfaction of any other condition is necessary
as a condition of, or in connection with the issuance or purchase of shares
thereunder, such option may not be exercised, in whole or in part, unless such
listing, registration, qualification, consent or approval, or satisfaction of
such condition shall have been effected or obtained on conditions acceptable to
the Board of Directors. Nothing herein shall be deemed to require the
Corporation to apply for or to obtain such listing, registration or
qualification, or to satisfy such condition.

         14. RIGHTS AS A STOCKHOLDER. The holder of an option shall have no
rights as a stockholder with respect to any shares covered by the option
(including, without limitation, any rights to receive dividends or non-cash
distributions with respect to such shares) until the date of issue of a stock
certificate to him or her for such shares. No adjustment shall be made for
dividends or other rights for which the record date is prior to the date such
stock certificate is issued.

         15. ADJUSTMENT PROVISIONS FOR RECAPITALIZATION,
             REORGANIZATIONS AND RELATED TRANSACTIONS.

(a)       Recapitalization and Related Transactions. If, through or as a result
of any recapitalization, reclassification, stock dividend, stock split, reverse
stock split or other similar transaction, (i) the outstanding shares of Common
Stock are increased, decreased or exchanged for a different number or kind of
shares or other securities of the Corporation, or (ii) additional shares or new
or different shares or other non-cash assets are distributed with respect to
such shares of Common Stock or other securities, an appropriate and
proportionate adjustment shall be made in (x) the maximum number and kind of
shares reserved for issuance under the Plan, (y) the number and kind of shares
or other securities subject to any then outstanding options under the Plan, and
(z) the price for each share subject to any then outstanding options under the
Plan, without changing the aggregate purchase price as to which such options
remain exercisable. Notwithstanding the foregoing, no adjustment shall be made
pursuant to this Section 15 if such adjustment (i) would cause the Plan to fail
to comply with Section 422 of the Code or with Rule 16b-3 or (ii) would be
considered as the adoption of a new plan requiring stockholder approval.

(b)       Reorganization, Merger and Related Transactions. If the Corporation
shall be the surviving corporation in any reorganization, merger or
consolidation of the Corporation with one or more other corporations, any then
outstanding option granted pursuant to the Plan shall pertain to and apply to
the securities to which a holder of the number of shares of Common Stock subject
to such options would have been entitled immediately following such
reorganization, merger, or consolidation, with a corresponding proportionate
adjustment of the purchase price as to which such options may be exercised so
that the aggregate purchase price as to which such options may be exercised
shall be the same as the aggregate purchase price as to which such options may
be exercised for the shares remaining subject to the options immediately prior
to such reorganization, merger, or consolidation.

(c)       Board Authority to Make Adjustments. Any adjustments made under this
Section 15 will be made by the Board of Directors, whose determination as to
what




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<PAGE>

adjustments, if any, will be made and the extent thereof will be final, binding
and conclusive. No fractional shares will be issued under the Plan on account of
any such adjustments.

         16. MERGER, CONSOLIDATION, ASSET SALE, LIQUIDATION, ETC.

(a)       General. In the event of a consolidation or merger in which the
Corporation is not the surviving corporation, or sale of all or substantially
all of the assets of the Corporation in which outstanding shares of Common Stock
are exchanged for securities, cash or other property of any other corporation or
business entity or in the event of a liquidation of the Corporation
(collectively, a "Corporate Transaction"), the Board of Directors of the
Corporation, or the board of directors of any corporation assuming the
obligations of the Corporation, may, in its discretion, take any one or more of
the following actions, as to outstanding options: (i) provide that such options
shall be assumed, or equivalent options shall be substituted, by the acquiring
or succeeding corporation (or an affiliate thereof), provided that any such
options substituted for Incentive Stock Options shall meet the requirements of
Section 424(a) of the Code, (ii) upon written notice to the optionees, provide
that all unexercised options will terminate immediately prior to the
consummation of such transaction unless exercised by the optionee within a
specified period following the date of such notice, (iii) in the event of a
Corporate Transaction under the terms of which holders of the Common Stock of
the Corporation will receive upon consummation thereof a cash payment for each
share surrendered in the Corporate Transaction (the "Transaction Price"), make
or provide for a cash payment to the optionees equal to the difference between
(A) the Transaction Price times the number of shares of Common Stock subject to
such outstanding options (to the extent then exercisable at prices not in excess
of the Transaction Price) and (B) the aggregate exercise price of all such
outstanding options in exchange for the termination of such options, and (iv)
provide that all or any outstanding options shall become exercisable in full
immediately prior to such event.

(b)       Substitute Options. The Corporation may grant options under the Plan
in substitution for options held by employees of another corporation who become
employees of the Corporation, or a subsidiary of the Corporation, as the result
of a merger or consolidation of the employing corporation with the Corporation
or a subsidiary of the Corporation, or as a result of the acquisition by the
Corporation, or one of its subsidiaries, of property or stock of the employing
corporation. The Corporation may direct that substitute options be granted on
such terms and conditions as the Board of Directors considers appropriate in the
circumstances.

         17. NO SPECIAL EMPLOYMENT RIGHTS. Nothing contained in the Plan or in
any option shall confer upon any optionee any right with respect to the
continuation of his or her employment by the Corporation or interfere in any way
with the right of the Corporation at any time to terminate such employment or to
increase or decrease the compensation of the optionee.

         18. OTHER EMPLOYEE BENEFITS. Except as to plans which by their terms
include such amounts as compensation, the amount of any compensation deemed to
be received by an employee as a result of the exercise of an option or the sale
of shares received upon such exercise will not constitute compensation with
respect to which any other employee benefits of such employee are determined,
including, without limitation,




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<PAGE>

benefits under any bonus, pension, profit-sharing, life insurance or salary
continuation plan, except as otherwise specifically determined by the Board of
Directors.

         19. AMENDMENT OF THE PLAN.

(a)       The Board of Directors may at any time, and from time to time, modify
or amend the Plan in any respect, except that if at any time the approval of the
stockholders of the Corporation is required under Section 422 of the Code or any
successor provision with respect to Incentive Stock Options, or under Rule
16b-3, the Board of Directors may not effect such modification or amendment
without such approval.

(b)       The termination or any modification or amendment of the Plan shall
not, without the consent of an optionee, affect his or her rights under an
option previously granted to him or her. With the consent of the optionee
affected, the Board of Directors may amend outstanding option agreements in a
manner not inconsistent with the Plan. The Board of Directors shall have the
right to amend or modify (i) the terms and provisions of the Plan and of any
outstanding Incentive Stock Options granted under the Plan to the extent
necessary to qualify any or all such options for such 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 (ii) the terms and
provisions of the Plan and of any outstanding option to the extent necessary to
ensure the qualification of the Plan under Rule 16b-3.

         20. WITHHOLDING.

(a)       The Corporation shall have the right to deduct from payments of any
kind otherwise due to the optionee any federal, state or local taxes of any kind
required by law to be withheld with respect to any shares issued upon exercise
of options under the Plan. Subject to the prior approval of the Corporation,
which may be withheld by the Corporation in its sole discretion, the optionee
may elect to satisfy such obligations, in whole or in part, (i) by causing the
Corporation to withhold shares of Common Stock otherwise issuable pursuant to
the exercise of an option or (ii) by delivering to the Corporation shares of
Common Stock already owned by the optionee. The shares so delivered or withheld
shall have a Fair Market Value equal to such withholding obligation as of the
date that the amount of tax to be withheld is to be determined. An optionee who
has made an election pursuant to this Section 20(a) may only satisfy his or her
withholding obligation with shares of Common Stock which are not subject to any
repurchase, forfeiture, unfulfilled vesting or other similar requirements.

(b)       The acceptance of shares of Common Stock upon exercise of an Incentive
Stock Option shall constitute an agreement by the optionee (i) to notify the
Corporation if any or all of such shares are disposed of by the optionee within
two years from the date the option was granted or within one year from the date
the shares were transferred to the optionee pursuant to the exercise of the
option, and (ii) if required by law, to remit to the Corporation, at the time of
and in the case of any such disposition, an amount sufficient to satisfy the
Corporation's federal, state and local withholding tax obligations with respect
to such disposition, whether or not, as to both (i) and (ii), the optionee is in
the employ of the Corporation at the time of such disposition.




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<PAGE>

(c)       Notwithstanding the foregoing, in the case of a Reporting Person whose
options have been granted in accordance with the provisions of Section 3(b)
herein, no election to use shares for the payment of withholding taxes shall be
effective unless made in compliance with any applicable requirements of Rule
16b-3.

         21. CANCELLATION AND NEW GRANT OF OPTIONS, ETC. The Board of Directors
shall have the authority to effect, at any time and from time to time, with the
consent of the affected optionees, (i) the cancellation of any or all
outstanding options under the Plan and the grant in substitution therefor of new
options under the Plan covering the same or different numbers of shares of
Common Stock and having an option exercise price per share which may be lower or
higher than the exercise price per share of the cancelled options or (ii) the
amendment of the terms of any and all outstanding options under the Plan to
provide an option exercise price per share which is higher or lower than the
then current exercise price per share of such outstanding options.

         22. EFFECTIVE DATE AND DURATION OF THE PLAN.

(a)       Effective Date. The Plan shall become effective when adopted by the
Board of Directors, but no Incentive Stock Option granted under the Plan shall
become exercisable unless and until the Plan shall have been approved by the
Corporation's stockholders. If such stockholder approval is not obtained within
twelve (12) months after the date of the Board's adoption of the Plan, no
options previously granted under the Plan shall be deemed to be Incentive Stock
Options and no Incentive Stock Options shall be granted thereafter. Amendments
to the Plan not requiring stockholder approval shall become effective when
adopted by the Board of Directors; amendments requiring stockholder approval (as
provided in Section 19) shall become effective when adopted by the Board of
Directors, but no Incentive Stock Option granted after the date of such
amendment shall become exercisable (to the extent that such amendment to the
Plan was required to enable the Corporation to grant such Incentive Stock Option
to a particular optionee) unless and until such amendment shall have been
approved by the Corporation's stockholders. If such stockholder approval is not
obtained within twelve (12) months of the Board's adoption of such amendment,
any Incentive Stock Options granted on or after the date of such amendment shall
terminate to the extent that such amendment to the Plan was required to enable
the Corporation to grant such option to a particular optionee. Subject to this
limitation, options may be granted under the Plan at any time after the
effective date and before the date fixed for termination of the Plan.

(b)       Termination. Unless sooner terminated in accordance with Section 16,
the Plan shall terminate upon the earlier of (i) the close of business on the
day next preceding the tenth anniversary of the date of is adoption by the Board
of Directors, or (ii) the date on which all shares available for issuance under
the Plan shall have been issued pursuant to the exercise or cancellation of
options granted under the Plan. If the date of termination is determined under
(i) above, then options outstanding on such date shall continue to have force
and effect in accordance with the provisions of the instruments evidencing such
options.

         23. PROVISION FOR FOREIGN PARTICIPANTS. The Board of Directors may,
without amending the Plan, modify awards or options granted to participants who
are foreign nationals or employed outside the United States to recognize
differences in laws,





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<PAGE>

rules, regulations or customs of such foreign jurisdictions with respect to tax,
securities, currency, employee benefit or other matters.

         24. GOVERNING LAW. The provisions of this Plan shall be governed and
construed in accordance with the laws of the State of New York without regard to
the principles of conflicts of laws.












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