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                                                                   Exhibit 10.18

                           DATA CRITICAL CORPORATION
                             1999 STOCK OPTION PLAN
                    (as amended and restated April 13, 2001)

   1. Purposes of the Plan. The purposes of this 1999 Stock Option Plan are to
attract and retain the best available personnel for positions of substantial
responsibility, to provide additional incentive to Employees and Consultants of
the Company and its Subsidiaries and to promote the success of the Company's
business. Options granted under the Plan may be incentive stock options (as
defined under Section 422 of the Code) or nonstatutory stock options, as
determined by the Administrator at the time of grant of an option and subject
to the applicable provisions of Section 422 of the Code, as amended, and the
regulations promulgated thereunder.

   2. Definitions. As used herein, the following definitions shall apply:

     (a) "Administrator" means the Board or any of its Committees appointed
  pursuant to Section 4 of the Plan.

     (b) "Affiliate" means an entity other than a Subsidiary (as defined
  below) in which the Company owns a significant interest, directly or
  indirectly, as determined in the discretion of the Committee, or which,
  together with the Company, is under common control of a third person or
  entity.

     (c) "Applicable Laws" means the legal requirements relating to the
  administration of stock option plans under applicable U.S. state corporate
  laws, U.S. federal and applicable state securities laws, the Code, any
  Stock Exchange rules or regulations and the applicable laws of any other
  country or jurisdiction where Options are granted under the Plan, as such
  laws, rules, regulations and requirements shall be in place from time to
  time; provided, however, that to the extent permitted under such laws,
  rules, regulations and requirements, the rights of any participant under
  the Plan shall be determined in accordance with the law of the State of
  California, without giving effect to principles of conflict of law.

     (d) "Board" means the Board of Directors of the Company.

     (e) "Change of Control" means a sale of all or substantially all of the
  Company's assets, or any merger or consolidation of the Company with or
  into another corporation other than a merger or consolidation in which the
  holders of more than 50% of the shares of capital stock of the Company
  outstanding immediately prior to such transaction continue to hold (either
  by the voting securities remaining outstanding or by their being converted
  into voting securities of the surviving entity) more than 50% of the total
  voting power represented by the voting securities of the Company, or such
  surviving entity, outstanding immediately after such transaction.

     (f) "Code" means the Internal Revenue Code of 1986, as amended.

     (g) "Committee" means one or more committees or subcommittees of the
  Board appointed by the Board to administer the Plan in accordance with
  Section 4 below.

     (h) "Common Stock" means the Common Stock of the Company.

     (i) "Company" means Data Critical Corporation, a Delaware corporation.

     (j) "Consultant" means any person, including an advisor, who renders
  services to the Company or any Parent, Subsidiary or Affiliate and is
  compensated for such services, and any Director of the Company whether
  compensated for such services or not.

     (k) "Continuous Service" means the absence of any interruption or
  termination of service as an Employee or Consultant to the Company or a
  Parent, Subsidiary or Affiliate. Continuous Service shall not be considered
  interrupted in the case of (i) sick leave; (ii) military leave; (iii) any
  other leave of absence approved by the Administrator, provided that such
  leave is for a period of not more than 90 days, unless reemployment upon
  the expiration of such leave is guaranteed by contract or statute, or
  unless provided otherwise pursuant to Company policy adopted from time to
  time; or (iv) transfers between locations of the Company or between the
  Company, its Parent(s), Subsidiaries, Affiliates or their respective
  successors.

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  Unless otherwise determined by the Administrator or the Company, a change
  in status from an Employee to a Consultant or from a Consultant to an
  Employee will not constitute a termination of Continuous Service Status.

     (l) "Corporate Transaction" means a sale of all or substantially all of
  the Company's assets, or a merger, consolidation or other capital
  reorganization of the Company with or into another corporation.

     (m) "Director" means a member of the Board.

     (n) "Employee" means any person (including, if appropriate, any Named
  Executive, Officer or Director) employed by the Company or any Parent,
  Subsidiary or Affiliate of the Company, with the status of employment
  determined based upon such minimum number of hours or periods worked as
  shall be determined by the Administrator in its discretion, subject to any
  requirements of the Code. The payment by the Company of a director's fee to
  a Director shall not be sufficient to constitute "employment" of such
  Director by the Company.

     (o) "Exchange Act" means the Securities Exchange Act of 1934, as
  amended.

     (p) "Fair Market Value" means, as of any date, the value of Common Stock
  determined as follows:

       (i) If the Common Stock is listed on any established stock exchange
    or a national market system including without limitation the National
    Market of the National Association of Securities Dealers, Inc. Automated
    Quotation ("Nasdaq") System, its Fair Market Value shall be the closing
    sales price for such stock (or the closing bid, if no sales were
    reported) as quoted on such system or exchange on the date of
    determination (or if no trading or bids occurred on the date of
    determination, on the last trading day prior to the date of
    determination), as reported in The Wall Street Journal or such other
    source as the Administrator deems reliable;

       (ii) If the Common Stock is quoted on the Nasdaq System (but not on
    the National Market thereof) or regularly quoted by a recognized
    securities dealer but selling prices are not reported, its Fair Market
    Value shall be the mean between the high bid and low asked prices for
    the Common Stock for the date of determination (or if no bids occurred
    on the date of determination, on the last trading day prior to the date
    of determination); or

       (iii) In the absence of an established market for the Common Stock,
    the Fair Market Value thereof shall be determined in good faith by the
    Administrator.

     (q) "Incentive Stock Option" means an Option intended to qualify as an
  incentive stock option within the meaning of Section 422 of the Code, as
  designated in the applicable Option Agreement.

     (r) "Listed Security" means any security of the Company that is listed
  or approved for listing on a national securities exchange or designated or
  approved for designation as a national market system security on an
  interdealer quotation system by the National Association of Securities
  Dealers, Inc.

     (s) "Named Executive" means any individual who, on the last day of the
  Company's fiscal year, is the chief executive officer of the Company (or is
  acting in such capacity) or among the four most highly compensated officers
  of the Company (other than the chief executive officer). Such officer
  status shall be determined pursuant to the executive compensation
  disclosure rules under the Exchange Act.

     (t) "Nonstatutory Stock Option" means an Option not intended to qualify
  as an Incentive Stock Option, as designated in the applicable Option
  Agreement.

     (u) "Officer" means a person who is an officer of the Company within the
  meaning of Section 16(a) of the Exchange Act and the rules and regulations
  promulgated thereunder.

     (v) "Option" means a stock option granted pursuant to the Plan.

     (w) "Option Agreement" means a written document, the form(s) of which
  shall be approved from time to time by the Administrator, reflecting the
  terms of an Option granted under the Plan and includes any documents
  attached to or incorporated into such Option Agreement, including, but not
  limited to, a notice of stock option grant and a form of exercise notice.

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     (x) "Option Exchange Program" means a program approved by the
  Administrator whereby outstanding Options are exchanged for Options with a
  lower exercise price.

     (y) "Optioned Stock" means the Common Stock subject to an Option.

     (z) "Optionee" means an Employee or Consultant who receives an Option.

     (aa) "Parent" means a "parent corporation," whether now or hereafter
  existing, as defined in Section 424(e) of the Code.

     (bb) "Participant" means any holder of one or more Options, or the
  Shares issuable or issued upon exercise of such Options, under the Plan.

     (cc) "Plan" means this 1999 Stock Option Plan.

     (dd) "Reporting Person" means an Officer, Director or greater than 10%
  stockholder of the Company within the meaning of Rule 16a-2 of the Exchange
  Act, who is required to file reports pursuant to Rule 16a-3 of the Exchange
  Act.

     (ee) "Rule 16b-3" means Rule 16b-3 promulgated under the Exchange Act,
  as amended from time to time, or any successor provision.

     (ff) "Share" means a share of the Common Stock, as adjusted in
  accordance with Section 15 of the Plan.

     (gg) "Stock Exchange" means any stock exchange or consolidated stock
  price reporting system on which prices for the Common Stock are quoted at
  any given time.

     (hh) "Subsidiary" means a "subsidiary corporation," whether now or
  hereafter existing, as defined in Section 424(f) of the Code.

     (ii) "Ten Percent Holder" means a person who owns stock representing
  more than ten percent (10%) of the voting power of all classes of stock of
  the Company or any Parent or Subsidiary.

   3. Stock Subject to the Plan. Subject to the provisions of Section 15 of the
Plan, the maximum aggregate number of shares that may be sold under the Plan is
1,750,000 Shares of Common Stock, plus an annual increase on the first day of
each of the Company's fiscal years beginning in 2002, 2003, 2004, 2005 and 2006
equal to the lesser of (i) 250,000 Shares, (ii) two percent (2%) of the Shares
outstanding on the last day of the immediately preceding fiscal year, or (iii)
such lesser number of Shares as is determined by the Board. The Shares may be
authorized, but unissued, or reacquired Common Stock.

   If an Option expires or becomes unexercisable for any reason without having
been exercised in full, or is surrendered pursuant to an Option Exchange
Program, the unpurchased Shares that were subject thereto shall, unless the
Plan has been terminated, become available for future grant under the Plan. In
addition, any Shares of Common Stock that are retained by the Company upon
exercise of an Option in order to satisfy the exercise or purchase price for
such Option or any withholding taxes due with respect to such exercise or
purchase shall be treated as not issued and shall continue to be available
under the Plan. Notwithstanding any other provision of the Plan, Shares issued
under the Plan and later repurchased by the Company pursuant to any repurchase
right that the Company may have shall not be available for future grant under
the Plan.

   4. Administration of the Plan.

     (a) General. The Plan shall be administered by the Board or a Committee,
  or a combination thereof, as determined by the Board. The Plan may be
  administered by different administrative bodies with respect to different
  classes of Participants and, if permitted by the Applicable Laws, the Board
  may authorize one or more officers (who may (but need not) be Officers) to
  grant Options to Employees and Consultants.

     (b) Administration with respect to Reporting Persons. With respect to
  Options granted to Reporting Persons and Named Executives, the Plan may
  (but need not) be administered so as to permit grants of

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  Options to Reporting Persons to qualify for the exemption set forth in Rule
  16b-3 and to qualify grants of Options to Named Executives as performance-
  based compensation under Section 162(m) of the Code, and otherwise so as to
  satisfy the Applicable Laws.

     (c) Committee Composition. If a Committee has been appointed pursuant to
  this Section 4, such Committee shall continue to serve in its designated
  capacity until otherwise directed by the Board. From time to time the Board
  may increase the size of any Committee and appoint additional members
  thereof, remove members (with or without cause) and appoint new members in
  substitution therefor, fill vacancies (however caused) and remove all
  members of a Committee and thereafter directly administer the Plan, all to
  the extent permitted by the Applicable Laws and, in the case of a Committee
  administering the Plan pursuant to Section 4(b) above, to the extent
  permitted or required by Rule 16b-3 and Section 162(m) of the Code.

     (d) Powers of the Administrator. Subject to the provisions of the Plan
  and in the case of a Committee, the specific duties delegated by the Board
  to such Committee, the Administrator shall have the authority, in its
  discretion:

       (i) to determine the Fair Market Value of the Common Stock, in
    accordance with Section 2(p) of the Plan;

       (ii) to select the Employees and Consultants to whom Options may
    from time to time be granted;

       (iii) to determine whether and to what extent Options are granted;

       (iv) to determine the number of Shares of Common Stock to be covered
    by each such Option granted;

       (v) to approve forms of agreement for use under the Plan;

       (vi) to determine the terms and conditions, not inconsistent with
    the terms of the Plan, of any award granted hereunder, which terms and
    conditions include but are not limited to the exercise or purchase
    price, the time or times when Options may be exercised (which may be
    based on performance criteria), any vesting acceleration or waiver of
    forfeiture restrictions, and any restriction or limitation regarding
    any Option, Optioned Stock, based in each case on such factors as the
    Administrator, in its sole discretion, shall determine;

       (vii) to determine whether and under what circumstances an Option
    may be settled in cash under Section 10(f) instead of Common Stock;

       (viii) to reduce the exercise price of any Option to the then
    current Fair Market Value if the Fair Market Value of the Common Stock
    covered by such Option shall have declined since the date the Option
    was granted and to make any other amendments or adjustments to any
    Option that the Administrator determines, in its discretion and under
    the authority granted to it under the Plan, to be necessary or
    advisable, provided however that no amendment or adjustment to an
    Option that would materially and adversely affect the rights of any
    Optionee shall be made without the prior written consent of the
    Optionee;

       (ix) to initiate an Option Exchange Program;

       (x) to construe and interpret the terms of the Plan and awards
    granted under the Plan; and

       (xi) in order to fulfill the purposes of the Plan and without
    amending the Plan, to modify grants of Options to Participants who are
    foreign nationals or employed outside of the United States in order to
    recognize differences in local law, tax policies or customs.

     (e) Effect of Administrator's Decision. All decisions, determinations
  and interpretations of the Administrator shall be final and binding on all
  Participants.

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   5. Eligibility.

     (a) Recipients of Grants. Nonstatutory Stock Options may be granted to
  Employees and Consultants. Incentive Stock Options may be granted only to
  Employees, provided however that Employees of Affiliates shall not be
  eligible to receive Incentive Stock Options. An Employee or Consultant who
  has been granted an Option may, if he or she is otherwise eligible, be
  granted additional Options.

     (b) Type of Option. Each Option shall be designated in the Option
  Agreement as either an Incentive Stock Option or a Nonstatutory Stock
  Option. However, notwithstanding such designations, to the extent that the
  aggregate Fair Market Value of Shares with respect to which Options are
  exercisable for the first time by an Optionee during any calendar year
  (under all plans of the Company or any Parent or Subsidiary) exceeds
  $100,000, such excess Options shall be treated as Nonstatutory Stock
  Options. For purposes of this Section 5(b), Incentive Stock Options shall
  be taken into account in the order in which they were granted, and the Fair
  Market Value of the Shares shall be determined as of the date of grant of
  such Option. In the event any Option designated as an Incentive Stock
  Option fails to meet the requirements set forth in this Plan for an
  Incentive Stock Option or as required to qualify as an incentive stock
  option within the meaning of Code Section 422, such Option shall not be
  void but instead shall be deemed a Nonstatutory Stock Option.

     (c) No Employment Rights. The Plan shall not confer upon any Participant
  any right with respect to continuation of employment or consulting
  relationship with the Company, nor shall it interfere in any way with his
  or her right or the Company's right to terminate his or her employment or
  consulting relationship at any time, with or without cause.

   6. Term of Plan. The Plan shall become effective upon its adoption by the
Board. It shall continue in effect for a term of ten (10) years unless sooner
terminated under Section 15 of the Plan.

   7. Term of Option. The term of each Option shall be the term stated in the
Option Agreement; provided however that the term shall be no more than ten (10)
years from the date of grant thereof or such shorter term as may be provided in
the Option Agreement and provided further that, in the case of an Incentive
Stock Option granted to a person who at the time of such grant is a Ten Percent
Holder, the term of such Incentive Stock Option shall be five (5) years from
the date of grant thereof or such shorter term as may be provided in the Option
Agreement.

   8. Limitation on Grants to Employees. Subject to adjustment as provided in
Section 12 below, the maximum number of Shares which may be subject to Options
granted to any one Employee under this Plan for any fiscal year of the Company
shall be 1,000,000.

   9. Option Exercise Price and Consideration.

     (a) Exercise Price. The per Share exercise price for the Shares to be
  issued pursuant to exercise of an Option shall be such price as is
  determined by the Administrator and set forth in the Option Agreement, but
  shall be subject to the following:

       (i) In the case of an Incentive Stock Option

         (A) granted to an Employee who at the time of grant is a Ten
      Percent Holder, the per Share exercise price shall be no less than
      110% of the Fair Market Value per Share on the date of grant; and

         (B) granted to any other Employee, the per Share exercise price
      shall be no less than 100% of the Fair Market Value per Share on the
      date of grant.

       (ii) In the case of a Nonstatutory Stock Option

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         (A) granted to a person who, at the time of the grant of such
      Option, is a Named Executive of the Company, the per share Exercise
      Price shall be no less than 100% of the Fair Market Value on the
      date of grant if such Option is intended to qualify as performance-
      based compensation under Section 162(m) of the Code; and

         (B) granted prior to the date on which the Common Stock becomes a
      Listed Security to a person who is at the time of grant is a Ten
      Percent Holder, the per Share exercise price shall be no less than
      110% of the Fair Market Value per Share on the date of grant if
      required by the Applicable Laws and, if not so required, shall be
      such price as is determined by the Administrator; and

         (C) granted prior to the date on which the Common Stock becomes a
      Listed Security to any person other than a Ten Percent Holder, the
      per Share exercise price shall be no less than 85% of the Fair
      Market Value per Share on the date of grant if required by
      Applicable Law and, if not so required, shall be such price as is
      determined by the Administrator.

       (iii) Notwithstanding the foregoing, Options may be granted with a
    per Share exercise price other than as required above pursuant to a
    Corporate Transaction.

       (b) Permissible Consideration. The consideration to be paid for the
    Shares to be issued upon exercise of an Option, including the method of
    payment, shall be determined by the Administrator (and, in the case of
    an Incentive Stock Option, shall be determined at the time of grant)
    and may consist entirely of (1) cash; (2) check; (3) delivery of
    Optionee's promissory note with such recourse, interest, security and
    redemption provisions as the Administrator determines to be appropriate
    (subject to provisions of Applicable Law); (4) cancellation of
    indebtedness; (5) surrender of other Shares that (x) in the case of
    Shares acquired upon exercise of an Option either have been owned by
    the Optionee for more than six months on the date of surrender (or such
    other period as may be required to avoid a charge to the Company's
    earnings) or were not acquired, directly or indirectly, from the
    Company, and (y) have a Fair Market Value on the date of surrender
    equal to the aggregate exercise price of the Shares as to which the
    Option is exercised; (6) authorization by the Optionee for the Company
    to retain from the total number of Shares as to which the Option is
    exercised that number of Shares having a Fair Market Value on the date
    of exercise equal to the exercise price for the total number of Shares
    as to which the Option is exercised; (7) delivery of a properly
    executed exercise notice together with such other documentation as the
    Administrator and the broker, if applicable, shall require to effect
    exercise of the Option and prompt delivery to the Company of the sale
    or loan proceeds required to pay the exercise price and any applicable
    withholding taxes; (8) any combination of the foregoing methods of
    payment; or (9) such other consideration and method of payment for the
    issuance of Shares to the extent permitted under the Applicable Laws.
    In making its determination as to the type of consideration to accept,
    the Administrator shall consider whether acceptance of such
    consideration may be reasonably expected to benefit the Company, and
    the Administrator may refuse to accept a particular form of
    consideration at the time of any Option exercise if, in its sole
    discretion, acceptance of such form of consideration is not in the best
    interests of the Company at such time.


   10. Exercise of Option.

     (a) Vesting. Any Option granted hereunder shall be exercisable at such
  times and under such conditions as determined by the Administrator,
  consistent with the terms of the Plan, and reflected in the Option
  Agreement, including vesting requirements and/or performance criteria with
  respect to the Company and/or the Optionee. The Administrator shall have
  the discretion to determine whether and to what extent the vesting of
  Options shall be tolled during any unpaid leave of absence; provided
  however that in the absence of such determination, vesting of Options shall
  be tolled during any such leave.

     (b) Procedure for Exercise. An Option may not be exercised for a
  fraction of a Share. An Option shall be deemed exercised when written
  notice of such exercise has been given to the Company in accordance with
  the terms of the Option by the person entitled to exercise the Option and
  the Company

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  has received full payment for the Shares with respect to which the Option
  is exercised. Full payment may, as authorized by the Administrator, consist
  of any consideration and method of payment allowable under Section 9(b) of
  the Plan. Exercise of an Option in any manner shall result in a decrease in
  the number of Shares that thereafter may be available, both for purposes of
  the Plan and for sale under the Option, by the number of Shares as to which
  the Option is exercised.

     (c) Rights as a Stockholder. Until the issuance (as evidenced by the
  appropriate entry on the books of the Company or of a duly authorized
  transfer agent of the Company) of the stock certificate evidencing such
  Shares, no right to vote or receive dividends or any other rights as a
  stockholder shall exist with respect to the Optioned Stock, notwithstanding
  the exercise of the Option. The Company shall issue (or cause to be issued)
  such stock certificate promptly upon exercise of the Option. No adjustment
  will be made for a dividend or other right for which the record date is
  prior to the date the stock certificate is issued, except as provided in
  Section 15 of the Plan.

     (d) Termination of Status as an Employee or Consultant. In the event of
  termination of an Optionee's Continuous Service Status, such Optionee may,
  but only within three (3) months (or such other period of time, not less
  than thirty (30) days, as is determined by the Administrator, with such
  determination in the case of an Incentive Stock Option being made at the
  time of grant of the Option) after the date of such termination (but in no
  event later than the date of expiration of the term of such Option as set
  forth in the Option Agreement), exercise his or her Option to the extent
  that he or she was entitled to exercise it at the date of such termination.
  To the extent that the Optionee was not entitled to exercise the Option at
  the date of such termination, or if the Optionee does not exercise the
  Option to the extent so entitled within the time specified above, the
  Option shall terminate and the Optioned Stock underlying the unexercised
  portion of the Option shall revert to the Plan. Unless otherwise determined
  by the Administrator or the Company, no termination shall be deemed to
  occur and this Section 10(b) shall not apply if (i) the Optionee is a
  Consultant who becomes an Employee, or (ii) the Optionee is an Employee who
  becomes a Consultant.

     (e) Disability of Optionee. Notwithstanding Section 10(b) above, in the
  event of termination of an Optionee's Continuous Service Status as a result
  of his or her total and permanent disability (as defined in Section
  22(e)(3) of the Code), such Optionee may, but only within twelve (12)
  months (or such other period of time as is determined by the Administrator,
  with such determination in the case of an Incentive Stock Option made at
  the time of grant of the Option) from the date of such termination (but in
  no event later than the date of expiration of the term of such Option as
  set forth in the Option Agreement), exercise the Option to the extent he or
  she was entitled to exercise it at the date of such termination. To the
  extent that the Optionee was not entitled to exercise the Option at the
  date of termination, or if the Optionee does not exercise the Option to the
  extent so entitled within the time specified above, the Option shall
  terminate and the Optioned Stock underlying the unexercised portion of the
  Option shall revert to the Plan.

     (f) Death of Optionee. In the event of the death of an Optionee during
  the period of Continuous Service Status since the date of grant of the
  Option, or within 30 days following termination of the Optionee's
  Continuous Service Status, the Option may be exercised at any time within
  twelve (12) months following the date of death (but in no event later than
  the expiration date of the term of such Option as set forth in the Option
  Agreement) by such Optionee's estate or by a person who acquired the right
  to exercise the Option by bequest or inheritance, but only to the extent of
  the right to exercise that had accrued at the date of death or, if earlier,
  the date of termination of the Optionee's Continuous Service Status. To the
  extent that the Optionee was not entitled to exercise the Option at the
  date of death or termination, as the case may be, or if the Optionee does
  not exercise such Option to the extent so entitled within the time
  specified above, the Option shall terminate and the Optioned Stock
  underlying the unexercised portion of the Option shall revert to the Plan.

     (g) Extension of Exercise Period. The Administrator shall have full
  power and authority to extend the period of time for which an Option is to
  remain exercisable following termination of an Optionee's Continuous
  Service Status from the periods set forth in Sections 10(d), 10(e) and
  10(f) above or in the

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  Option Agreement to such greater time as the Administrator shall deem
  appropriate, provided that in no event shall such Option be exercisable
  later than the date of expiration of the term of such Option as set forth
  in the Option Agreement.

     (h) Buy-Out Provisions. The Administrator may at any time offer to buy
  out for a payment in cash or Shares an Option previously granted under the
  Plan based on such terms and conditions as the Administrator shall
  establish and communicate to the Optionee at the time such offer is made.

   11. Taxes.

     (a) As a condition of the exercise of an Option granted under the Plan,
  the Participant (or in the case of the Participant's death, the person
  exercising the Option) shall make such arrangements as the Administrator
  may require for the satisfaction of any applicable federal, state, local or
  foreign withholding tax obligations that may arise in connection with the
  exercise of Option and the issuance of Shares. The Company shall not be
  required to issue any Shares under the Plan until such obligations are
  satisfied.

     (b) In the case of an Employee and in the absence of any other
  arrangement, the Employee shall be deemed to have directed the Company to
  withhold or collect from his or her compensation an amount sufficient to
  satisfy such tax obligations from the next payroll payment otherwise
  payable after the date of an exercise of the Option.

     (c) This Section 11(c) shall apply only after the date, if any, upon
  which the Common Stock becomes a Listed Security. In the case of
  Participant other than an Employee (or in the case of an Employee where the
  next payroll payment is not sufficient to satisfy such tax obligations,
  with respect to any remaining tax obligations), in the absence of any other
  arrangement and to the extent permitted under the Applicable Laws, the
  Participant shall be deemed to have elected to have the Company withhold
  from the Shares to be issued upon exercise of the Option that number of
  Shares having a Fair Market Value determined as of the applicable Tax Date
  (as defined below) equal to the amount required to be withheld. For
  purposes of this Section 11, the Fair Market Value of the Shares to be
  withheld shall be determined on the date that the amount of tax to be
  withheld is to be determined under the Applicable Laws (the "Tax Date").

     (d) At the discretion of the Administrator, a Participant may satisfy
  his or her tax withholding obligations arising in connection with an Option
  by one or some combination of the following methods: (i) cash payment; (ii)
  payroll deduction out of the Optionee's current compensation; or (iii) if
  permitted by the Administrator, in its discretion, a Participant may
  satisfy his or her tax withholding obligations upon exercise of an Option
  by surrendering to the Company Shares that (A) in the case of Shares
  previously acquired from the Company, have been owned by the Participant
  for more than six (6) months on the date of surrender, and (B) have a Fair
  Market Value determined as of the applicable Tax Date equal to the amount
  required to be withheld.

     (e) Any election or deemed election by a Participant to have Shares
  withheld to satisfy tax withholding obligations under Section 11(c) or (d)
  above shall be irrevocable as to the particular Shares as to which the
  election is made and shall be subject to the consent or disapproval of the
  Administrator. Any election by a Participant under Section 11(d) above must
  be made on or prior to the applicable Tax Date.

     (f) In the event an election to have Shares withheld is made by a
  Participant and the Tax Date is deferred under Section 83 of the Code
  because no election is filed under Section 83(b) of the Code, the
  Participant shall receive the full number of Shares with respect to which
  the Option is exercised but such Participant shall be unconditionally
  obligated to tender back to the Company the proper number of Shares on the
  Tax Date.

   12. Non-Transferability of Options. Options may not be transferred or
disposed of in any manner other than by will or by the laws of descent or
distribution or pursuant to a domestic relations order (as defined by the Code
or the rules thereunder); provided that, after the date, if any, upon which the
Common Stock becomes a Listed Security, the Administrator may in its discretion
grant transferable Nonstatutory Stock Options pursuant to Option Agreements
specifying (i) the manner in which such Nonstatutory Stock Options are

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transferable and (ii) that any such transfer shall be subject to the Applicable
Laws. The designation of a beneficiary by an Optionee will not constitute a
transfer. An Option may be exercised, during the lifetime of the holder of
Option, only by such holder or a transferee permitted by this Section 12.

   13. Time of Granting Options. The date of grant of an Option shall, for all
purposes, be the date on which the Administrator makes the determination
granting such Option, or such later date as is determined by the Administrator;
provided however that in the case of an Incentive Stock Option, the grant date
shall be the later of the date on which the Administrator makes the
determination granting such Incentive Stock Option or the date of commencement
of the Optionee's employment relationship with the Company. Notice of the
determination shall be given to each Employee or Consultant to whom an Option
is so granted within a reasonable time after the date of such grant.

   14. Adjustments Upon Changes in Capitalization, Corporate Transactions and
Certain Other Transactions.

     (a) Changes in Capitalization. Subject to any required action by the
  stockholders of the Company, the number of shares of Common Stock covered
  by each outstanding Option, the number of Shares set forth in Sections 3
  and 8 above, and the number of shares of Common Stock that have been
  authorized for issuance under the Plan but as to which no Options have yet
  been granted or that have been returned to the Plan upon cancellation or
  expiration of an Option, as well as the price per Share of Common Stock
  covered by each such outstanding Option, shall be proportionately adjusted
  for any increase or decrease in the number of issued Shares of Common Stock
  resulting from a stock split, reverse stock split, stock dividend,
  combination, recapitalization or reclassification of the Common Stock
  (including any change in the number of Shares of Common Stock effected in
  connection with a change of domicile of the Company), or any other increase
  or decrease in the number of issued Shares of Common Stock effected without
  receipt of consideration by the Company; provided however that conversion
  of any convertible securities of the Company shall not be deemed to have
  been "effected without receipt of consideration." Such adjustment shall be
  made by the Administrator, whose determination in that respect shall be
  final, binding and conclusive. 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 of Common Stock subject to an Option.

     (b) Dissolution or Liquidation. In the event of the dissolution or
  liquidation of the Company that is not a Corporate Transaction, each
  outstanding Option shall terminate immediately upon the consummation of
  such dissolution or liquidation, unless otherwise provided by the
  Administrator.

     (c) Acceleration of Vesting Upon a Change of Control.

       (i) In the event of a Change in Control, the vesting of each
    outstanding Option shall automatically be accelerated so that fifty
    percent (50%) of the unvested shares of Common Stock covered by such
    Option shall be fully vested upon the consummation of the Change in
    Control; provided, however, that the vesting of such Option shall only
    be accelerated to the extent that a maximum of fifty percent (50%) of
    the total unvested shares of Common Stock covered by all options held
    by Optionee (including options issued pursuant to the Company's 1994
    Stock Option Plan and shares of Common Stock issued upon exercise of
    options that are subject to a Company right of first refusal) are
    accelerated and become fully vested as a result of the Change in
    Control.

       (ii) The vesting of each outstanding Option held by an Optionee
    shall be accelerated completely so that one hundred percent (100%) of
    the shares of Common Stock covered by such Option are fully vested and
    exercisable in the event that (A) such Optionee is an Executive Officer
    (as defined below) immediately prior to the consummation of a Change of
    Control and (B) within twelve (12) months of the consummation of such
    Change of Control, such Optionee's employment by the Company is either
    terminated by the Company other than for Cause (as defined below) or
    terminated by the Optionee for Good Reason (as defined below).

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<PAGE>

   For purposes of this Section 14c)(ii), "Executive Officer" means any officer
of the Company designated as Vice President or any title senior thereto.

   For purposes of this Section 14c)(ii), "Cause" means fraud, misappropriation
or embezzlement on the part of the Optionee which results in material loss,
damage or injury to the Company, the Optionee's conviction of a felony
involving moral turpitude, or the Optionee's gross neglect of duties.

   For purposes of this Section 14c)(ii), "Good Reason" means a material
reduction in compensation or a relocation of the Optionee's principal worksite
to a location more than 50 miles from the Optionee's pre-Change of Control
worksite or a material reduction in responsibilities or authority as in effect
before the Change of Control.

       (iii) The Administrator shall have the authority, in the
    Administrator's sole discretion, to provide for the automatic
    acceleration of any outstanding Option upon the occurrence of a Change
    in Control, but only to the extent that such acceleration does not
    interfere with any "pooling of interests" accounting treatment used in
    connection with the Change in Control.

     (d) Corporate Transactions; Change of Control. In the event of a
  Corporate Transaction, including a Change of Control, the Administrator
  shall, as to outstanding Options, either (i) provide that such Options
  shall be assumed by the by the successor corporation or a Parent or
  Subsidiary of such successor corporation (such entity, the "Successor
  Corporation") or that the Successor Corporation shall substitute with
  respect to such Options equivalent options; (ii) provide upon notice to
  Optionees that all Options, to the extent then exercisable or to be
  exercisable as a result of the Change of Control, must be exercised on or
  before a specified date (which date shall be at least five (5) days from
  the date of the notice), after which the Options shall terminate; or (iii)
  terminate each Option in its entirety in exchange for a payment of cash,
  securities and/or other property equal to the excess of the Fair Market
  Value of the Shares with respect to which the Option is vested and
  exercisable immediately prior to the consummation of the transaction over
  the aggregate exercise price thereof. In the event of a Change of Control,
  all conditions and restrictions with respect to shares of restricted stock
  shall lapse, except to the extent such conditions and restrictions are
  assigned to the successor corporation (or its Parent) in connection with
  the Change of Control.

   For purposes of this Section 14d), an Option shall be considered assumed,
without limitation, if, at the time of issuance of the stock or other
consideration upon a Corporate Transaction or a Change of Control, as the case
may be, each holder of an Option would be entitled to receive upon exercise of
the Option the same number and kind of shares of stock or the same amount of
property, cash or securities as such holder would have been entitled to receive
upon the occurrence of the transaction if the holder had been, immediately
prior to such transaction, the holder of the number of Shares of Common Stock
covered by the Option at such time (after giving effect to any adjustments in
the number of Shares covered by the Option as provided for in this Section 14;
provided however that if the consideration received in the transaction is not
solely common stock of the Successor Corporation, the Administrator may, with
the consent of the Successor Corporation, provide for the consideration to be
received upon exercise of the Option to be solely common stock of the Successor
Corporation equal to the Fair Market Value of the per Share consideration
received by holders of Common Stock in the transaction.

     (e) Certain Distributions. In the event of any distribution to the
  Company's stockholders of securities of any other entity or other assets
  (other than dividends payable in cash or stock of the Company) without
  receipt of consideration by the Company, the Administrator may, in its
  discretion, appropriately adjust the price per Share of Common Stock
  covered by each outstanding Option to reflect the effect of such
  distribution.

   15. Amendment and Termination of the Plan. The Board may at any time amend,
alter, suspend, discontinue or terminate the Plan, but no amendment,
alteration, suspension, discontinuance or termination (other than an adjustment
made pursuant to Section 14 above) shall be made that would materially and
adversely affect the rights of any Optionee under any outstanding grant,
without his or her consent. Such

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<PAGE>

consent shall be evidenced in writing signed by such Optionee or holder and the
Company. In addition, to the extent necessary and desirable to comply with the
Applicable Laws, the Company shall obtain stockholder approval of any Plan
amendment in such a manner and to such as degree as required.

   16. Conditions Upon Issuance of Shares. Notwithstanding any other provision
of the Plan or any agreement entered into by the Company pursuant to the Plan,
the Company shall not be obligated, and shall have no liability for failure, to
issue or deliver any Shares under the Plan unless such issuance or delivery
would comply with the Applicable Laws, with such compliance determined by the
Company in consultation with its legal counsel.

   As a condition to the exercise of an Option, the Company may require the
person exercising such Option to represent and warrant at the time of any such
exercise that the Shares are being purchased only for investment and without
any present intention to sell or distribute such Shares if, in the opinion of
counsel for the Company, such a representation is required by Applicable Laws.

   17. Reservation of Shares. The Company, during the term of this Plan, will
at all times reserve and keep available such number of Shares as shall be
sufficient to satisfy the requirements of the Plan.

   18. Agreements. Options shall be evidenced by Option Agreements in such
form(s) as the Administrator shall from time to time approve.

   19. Stockholder Approval. If required by the Applicable Laws, continuance of
the Plan shall be subject to approval by the stockholders of the Company within
twelve (12) months before or after the date the Plan is adopted. Such
stockholder approval shall be obtained in the manner and to the degree required
under the Applicable Laws.

   20. Information and Documents to Optionees and Purchasers. Prior to the date
upon which the Common Stock becomes a Listed Security and if required by the
Applicable Laws, the Company shall provide financial statements at least
annually to each Optionee and to each individual who acquired Shares pursuant
to the Plan, during the period such Optionee or purchaser has one or more
Options outstanding, and in the case of an individual who acquired Shares
pursuant to the Plan, during the period such individual owns such Shares. The
Company shall not be required to provide such information if the issuance of
Options under the Plan is limited to key employees whose duties in connection
with the Company assure their access to equivalent information.

   21. Effective Time. The Plan's effective date is the date on which it is
approved by the Company's stockholders. The Board amended Section 3 of the Plan
on April 13, 2001, which amendment was approved by the stockholders on       ,
2001.

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