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                                                                    EXHIBIT 10.6

                                 STENTOR, INC.

                        2005 EMPLOYEE STOCK PURCHASE PLAN

                            ADOPTED: JANUARY 19, 2005
                    APPROVED BY STOCKHOLDERS: ________, 2005

1. GENERAL.

      (a) The purpose of the Plan is to provide a means by which Employees of
the Company and certain designated Related Corporations may be given an
opportunity to purchase shares of the Common Stock of the Company.

      (b) The Company, by means of the Plan, seeks to retain the services of
such Employees, to secure and retain the services of new Employees and to
provide incentives for such persons to exert maximum efforts for the success of
the Company and its Related Corporations.

      (c) The Company intends that the Purchase Rights be considered options
issued under an Employee Stock Purchase Plan.

2. DEFINITIONS.

      As used in the Plan, the following definitions shall apply to the
capitalized terms indicated below:

      (a) "BOARD" means the Board of Directors of the Company.

      (b) "CAPITALIZATION ADJUSTMENT" has the meaning ascribed to that term in
Section 14(a).

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

      (d) "COMMITTEE" means a committee of one (1) or more members of the Board
to whom authority has been delegated by the Board in accordance with Section
3(c).

      (e) "COMMON STOCK" means the common stock of the Company.

      (f) "COMPANY" means Stentor, Inc., a Delaware corporation.

      (g) "CONTRIBUTIONS" means the payroll deductions and other additional
payments specifically provided for in the Offering, that a Participant
contributes to fund the exercise of a Purchase Right. A Participant may make
additional payments into his or her account, if specifically provided for in the
Offering, and then only if the Participant has not already had the maximum
permitted amount withheld during the Offering through payroll deductions.

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      (h) "CORPORATE TRANSACTION" means the occurrence, in a single transaction
or in a series of related transactions, of any one or more of the following
events:

            (i) a sale or other disposition of all or substantially all, as
determined by the Board in its sole discretion, of the consolidated assets of
the Company and its Subsidiaries;

            (ii) a sale or other disposition of at least ninety percent (90%) of
the outstanding securities of the Company;

            (iii) the consummation of a merger, consolidation or similar
transaction following which the Company is not the surviving corporation; or

            (iv) the consummation of a merger, consolidation or similar
transaction following which the Company is the surviving corporation but the
shares of Common Stock outstanding immediately preceding the merger,
consolidation or similar transaction are converted or exchanged by virtue of the
merger, consolidation or similar transaction into other property, whether in the
form of securities, cash or otherwise.

      (i) "DIRECTOR" means a member of the Board.

      (j) "ELIGIBLE EMPLOYEE" means an Employee who meets the requirements set
forth in the Offering for eligibility to participate in the Offering, provided
that such Employee also meets the requirements for eligibility to participate
set forth in the Plan.

      (k) "EMPLOYEE" means any person, including Officers and Directors, who is
employed for purposes of Section 423(b)(4) of the Code by the Company or a
Related Corporation. However, service solely as a Director, or payment of a fee
for such services, shall not cause a Director to be considered an "Employee" for
purposes of the Plan.

      (l) "EMPLOYEE STOCK PURCHASE PLAN" means a plan that grants Purchase
Rights intended to be options issued under an "employee stock purchase plan," as
that term is defined in Section 423(b) of the Code.

      (m) "EXCHANGE ACT" means the Securities Exchange Act of 1934, as amended.

      (n) "FAIR MARKET VALUE" means, as of any date, the value of the Common
Stock determined as follows:

            (i) If the Common Stock is listed on any established stock exchange
or traded on the Nasdaq National Market or the Nasdaq SmallCap Market, the Fair
Market Value of a share of Common Stock shall be the closing sales price for
such stock (or the closing bid, if no sales were reported) as quoted on such
exchange or market (or the exchange or market with the greatest volume of
trading in the Common Stock) on the date in question, as reported in The Wall
Street Journal or such other source as the Board deems reliable.

            (ii) In the absence of such markets for the Common Stock, the Fair
Market Value shall be determined by the Board in good faith.

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      (o) "IPO DATE" means the date of the underwriting agreement between the
Company and the underwriter(s) managing the initial public offering of the
Common Stock, pursuant to which the Common Stock is priced for the initial
public offering.

      (p) "OFFERING" means the grant of Purchase Rights to purchase shares of
Common Stock under the Plan to Eligible Employees.

      (q) "OFFERING DATE" means a date selected by the Board for an Offering to
commence.

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

      (s) "PARTICIPANT" means an Eligible Employee who holds an outstanding
Purchase Right granted pursuant to the Plan.

      (t) "PLAN" means this Stentor, Inc. 2005 Employee Stock Purchase Plan.

      (u) "PURCHASE DATE" means one or more dates during an Offering established
by the Board on which Purchase Rights shall be exercised and as of which
purchases of shares of Common Stock shall be carried out in accordance with such
Offering.

      (v) "PURCHASE PERIOD" means a period of time specified within an Offering
beginning on the Offering Date or on the next day following a Purchase Date
within an Offering and ending on a Purchase Date. An Offering may consist of one
or more Purchase Periods.

      (w) "PURCHASE RIGHT" means an option to purchase shares of Common Stock
granted pursuant to the Plan.

      (x) "RELATED CORPORATION" means any "parent corporation" or "subsidiary
corporation" of the Company whether now or subsequently established, as those
terms are defined in Sections 424(e) and (f), respectively, of the Code.

      (y) "SECURITIES ACT" means the Securities Act of 1933, as amended.

      (z) "TRADING DAY" means any day on which the exchange(s) or market(s) on
which shares of Common Stock are listed, whether it be an established stock
exchange, the Nasdaq National Market, the Nasdaq SmallCap Market or otherwise,
is open for trading.

3. ADMINISTRATION.

      (a) The Board shall administer the Plan unless and until the Board
delegates administration of the Plan to a Committee, as provided in Section
3(c).

      (b) The Board shall have the power, subject to, and within the limitations
of, the express provisions of the Plan:

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            (i) To determine when and how Purchase Rights to purchase shares of
Common Stock shall be granted and the provisions of each Offering of such
Purchase Rights (which need not be identical).

            (ii) To designate from time to time which Related Corporations of
the Company shall be eligible to participate in the Plan.

            (iii) To construe and interpret the Plan and Purchase Rights, and to
establish, amend and revoke rules and regulations for its administration. The
Board, in the exercise of this power, may correct any defect, omission or
inconsistency in the Plan, in a manner and to the extent it shall deem necessary
or expedient to make the Plan fully effective.

            (iv) To adopt such procedures and sub-plans as are necessary or
appropriate to permit participation in the Plan by Employees who are foreign
nationals or employed outside the United States.

            (v) To amend the Plan as provided in Section 15.

            (vi) Generally, to exercise such powers and to perform such acts as
it deems necessary or expedient to promote the best interests of the Company and
its Related Corporations and to carry out the intent that the Plan be treated as
an Employee Stock Purchase Plan.

      (c) The Board may delegate some or all of the administration of the Plan
to a Committee or Committees. If administration is delegated to a Committee, the
Committee shall have, in connection with the administration of the Plan, the
powers theretofore possessed by the Board that have been delegated to the
Committee, including the power to delegate to a subcommittee any of the
administrative powers the Committee is authorized to exercise (and references in
this Plan to the Board shall thereafter be to the Committee or subcommittee),
subject, however, to such resolutions, not inconsistent with the provisions of
the Plan, as may be adopted from time to time by the Board. The Board may retain
the authority to concurrently administer the Plan with the Committee and may, at
any time, revest in the Board some or all of the powers previously delegated.

      (d) All determinations, interpretations and constructions made by the
Board in good faith shall not be subject to review by any person and shall be
final, binding and conclusive on all persons.

4. SHARES OF COMMON STOCK SUBJECT TO THE PLAN.

      (a) Subject to the provisions of Section 14(a) relating to Capitalization
Adjustments, the shares of Common Stock that may be sold pursuant to Purchase
Rights shall not exceed in the aggregate one million (1,000,000) shares of
Common Stock. In addition, the number of shares of Common Stock available for
issuance under the Plan shall automatically increase on January 1st of each
year, commencing in 2006 and ending on (and including) January 1, 2015, in an
amount equal to the lesser of (i) one and one-half percent (1.5%) of the total
number of shares of Common Stock outstanding on December 31st of the preceding
calendar year, or (ii) four hundred fifty thousand (450,000) shares of Common
Stock. Notwithstanding the foregoing, the Board may act prior to the first day
of any calendar year, to provide that there shall be no

                                       4.
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increase in the share reserve for such calendar year or that the increase in the
share reserve for such calendar year shall be a lesser number of shares of
Common Stock than would otherwise occur pursuant to the preceding sentence.

      (b) If any Purchase Right granted under the Plan shall for any reason
terminate without having been exercised, the shares of Common Stock not
purchased under such Purchase Right shall again become available for issuance
under the Plan.

      (c) The stock purchasable under the Plan shall be shares of authorized but
unissued or reacquired Common Stock, including shares repurchased by the Company
on the open market.

5. GRANT OF PURCHASE RIGHTS; OFFERING.

      (a) The Board may from time to time grant or provide for the grant of
Purchase Rights to purchase shares of Common Stock under the Plan to Eligible
Employees in an Offering (consisting of one or more Purchase Periods) on an
Offering Date or Offering Dates selected by the Board. Each Offering shall be in
such form and shall contain such terms and conditions as the Board shall deem
appropriate, which shall comply with the requirement of Section 423(b)(5) of the
Code that all Employees granted Purchase Rights shall have the same rights and
privileges. The terms and conditions of an Offering shall be incorporated by
reference into the Plan and treated as part of the Plan. The provisions of
separate Offerings need not be identical, but each Offering shall include
(through incorporation of the provisions of this Plan by reference in the
document comprising the Offering or otherwise) the period during which the
Offering shall be effective, which period shall not exceed twenty-seven (27)
months beginning with the Offering Date, and the substance of the provisions
contained in Sections 6 through 9, inclusive.

      (b) If a Participant has more than one Purchase Right outstanding under
the Plan, unless he or she otherwise indicates in agreements or notices
delivered hereunder: (i) each agreement or notice delivered by that Participant
shall be deemed to apply to all of his or her Purchase Rights under the Plan,
and (ii) a Purchase Right with a lower exercise price (or an earlier-granted
Purchase Right, if different Purchase Rights have identical exercise prices)
shall be exercised to the fullest possible extent before a Purchase Right with a
higher exercise price (or a later-granted Purchase Right if different Purchase
Rights have identical exercise prices) shall be exercised.

      (c) The Board shall have the discretion to structure an Offering so that
if the Fair Market Value of the shares of Common Stock on the first day of a new
Purchase Period within that Offering is less than or equal to the Fair Market
Value of the shares of Common Stock on the Offering Date, then (i) that Offering
shall terminate immediately, and (ii) the Participants in such terminated
Offering shall be automatically enrolled in a new Offering beginning on the
first day of such new Purchase Period.

6. ELIGIBILITY.

      (a) Purchase Rights may be granted only to Employees of the Company or, as
the Board may designate as provided in Section 3(b), to Employees of a Related
Corporation. Except as provided in Section 6(b), an Employee shall not be
eligible to be granted Purchase Rights under the Plan unless, on the Offering
Date, such Employee has been in the employ of the

                                       5.
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Company or the Related Corporation, as the case may be, for such continuous
period preceding such Offering Date as the Board may require, but in no event
shall the required period of continuous employment be greater than two (2)
years. In addition, the Board may provide that no Employee shall be eligible to
be granted Purchase Rights under the Plan unless, on the Offering Date, such
Employee's customary employment with the Company or the Related Corporation is
more than twenty (20) hours per week and more than five (5) months per calendar
year or such other criteria as the Board may determine consistent with Section
423 of the Code.

      (b) The Board may provide that each person who, during the course of an
Offering, first becomes an Eligible Employee shall, on a date or dates specified
in the Offering which coincides with the day on which such person becomes an
Eligible Employee or which occurs thereafter, receive a Purchase Right under
that Offering, which Purchase Right shall thereafter be deemed to be a part of
that Offering. Such Purchase Right shall have the same characteristics as any
Purchase Rights originally granted under that Offering, as described herein,
except that:

            (i) the date on which such Purchase Right is granted shall be the
"Offering Date" of such Purchase Right for all purposes, including determination
of the exercise price of such Purchase Right;

            (ii) the period of the Offering with respect to such Purchase Right
shall begin on its Offering Date and end coincident with the end of such
Offering; and

            (iii) the Board may provide that if such person first becomes an
Eligible Employee within a specified period of time before the end of the
Offering, he or she shall not receive any Purchase Right under that Offering.

      (c) No Employee shall be eligible for the grant of any Purchase Rights
under the Plan if, immediately after any such Purchase Rights are granted, such
Employee owns stock possessing five percent (5%) or more of the total combined
voting power or value of all classes of stock of the Company or of any Related
Corporation. For purposes of this Section 6(c), the rules of Section 424(d) of
the Code shall apply in determining the stock ownership of any Employee, and
stock which such Employee may purchase under all outstanding Purchase Rights and
options shall be treated as stock owned by such Employee.

      (d) As specified by Section 423(b)(8) of the Code, an Eligible Employee
may be granted Purchase Rights under the Plan only if such Purchase Rights,
together with any other rights granted under all Employee Stock Purchase Plans
of the Company and any Related Corporations, do not permit such Eligible
Employee's rights to purchase stock of the Company or any Related Corporation to
accrue at a rate which exceeds twenty five thousand dollars ($25,000) of Fair
Market Value of such stock (determined at the time such rights are granted, and
which, with respect to the Plan, shall be determined as of their respective
Offering Dates) for each calendar year in which such rights are outstanding at
any time.

      (e) Officers of the Company and any designated Related Corporation, if
they are otherwise Eligible Employees, shall be eligible to participate in
Offerings under the Plan. Notwithstanding the foregoing, the Board may provide
in an Offering that Employees who are

                                       6.
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highly compensated Employees within the meaning of Section 423(b)(4)(d) of the
Code shall not be eligible to participate.

7. PURCHASE RIGHTS; PURCHASE PRICE.

      (a) On each Offering Date, each Eligible Employee, pursuant to an Offering
made under the Plan, shall be granted a Purchase Right to purchase up to that
number of shares of Common Stock purchasable either with a percentage or with a
maximum dollar amount, as designated by the Board, but in either case not
exceeding fifteen percent (15%) of such Employee's earnings (as defined by the
Board in each Offering) during the period that begins on the Offering Date (or
such later date as the Board determines for a particular Offering) and ends on
the date stated in the Offering, which date shall be no later than the end of
the Offering.

      (b) The Board shall establish one (1) or more Purchase Dates during an
Offering as of which Purchase Rights granted pursuant to that Offering shall be
exercised and purchases of shares of Common Stock shall be carried out in
accordance with such Offering.

      (c) In connection with each Offering made under the Plan, the Board may
specify a maximum number of shares of Common Stock that may be purchased by any
Participant on any Purchase Date during such Offering. In connection with each
Offering made under the Plan, the Board may specify a maximum aggregate number
of shares of Common Stock that may be purchased by all Participants pursuant to
such Offering. In addition, in connection with each Offering that contains more
than one Purchase Date, the Board may specify a maximum aggregate number of
shares of Common Stock that may be purchased by all Participants on any Purchase
Date under the Offering. If the aggregate purchase of shares of Common Stock
issuable upon exercise of Purchase Rights granted under the Offering would
exceed any such maximum aggregate number, then, in the absence of any Board
action otherwise, a pro rata allocation of the shares of Common Stock available
shall be made in as nearly a uniform manner as shall be practicable and
equitable.

      (d) The purchase price of shares of Common Stock acquired pursuant to
Purchase Rights shall be not less than the lesser of:

            (i) an amount equal to eighty-five percent (85%) of the Fair Market
Value of the shares of Common Stock on the Offering Date; or

            (ii) an amount equal to eighty-five percent (85%) of the Fair Market
Value of the shares of Common Stock on the applicable Purchase Date.

8. PARTICIPATION; WITHDRAWAL; TERMINATION.

      (a) A Participant may elect to authorize payroll deductions pursuant to an
Offering under the Plan by completing and delivering to the Company, within the
time specified in the Offering, an enrollment form (in such form as the Company
may provide). Each such enrollment form shall authorize an amount of
Contributions expressed as a percentage of the submitting Participant's earnings
(as defined in each Offering) during the Offering (not to exceed the maximum
percentage specified by the Board). Each Participant's Contributions shall be
credited to a bookkeeping account for such Participant under the Plan and shall
be deposited with the

                                       7.
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general funds of the Company except where applicable law requires that
Contributions be deposited with a third party. To the extent provided in the
Offering, a Participant may begin such Contributions after the beginning of the
Offering. To the extent provided in the Offering, a Participant may thereafter
reduce (including to zero) or increase his or her Contributions. To the extent
specifically provided in the Offering, in addition to making Contributions by
payroll deductions, a Participant may make Contributions through the payment by
cash or check prior to each Purchase Date of the Offering.

      (b) During an Offering, a Participant may cease making Contributions and
withdraw from the Offering by delivering to the Company a notice of withdrawal
in such form as the Company may provide. Such withdrawal may be elected at any
time prior to the end of the Offering, except as provided otherwise in the
Offering. Upon such withdrawal from the Offering by a Participant, the Company
shall distribute to such Participant all of his or her accumulated Contributions
(reduced to the extent, if any, such Contributions have been used to acquire
shares of Common Stock for the Participant) under the Offering, and such
Participant's Purchase Right in that Offering shall thereupon terminate. A
Participant's withdrawal from an Offering shall have no effect upon such
Participant's eligibility to participate in any other Offerings under the Plan,
but such Participant shall be required to deliver a new enrollment form in order
to participate in subsequent Offerings.

      (c) Purchase Rights granted pursuant to any Offering under the Plan shall
terminate immediately upon a Participant ceasing to be an Employee for any
reason or for no reason (subject to any post-employment participation period
required by law) or other lack of eligibility. The Company shall distribute to
such terminated or otherwise ineligible Employee all of his or her accumulated
Contributions (reduced to the extent, if any, such Contributions have been used
to acquire shares of Common Stock for the terminated or otherwise ineligible
Employee) under the Offering.

      (d) Purchase Rights shall not be transferable by a Participant except by
will, the laws of descent and distribution, or by a beneficiary designation as
provided in Section 13. During a Participant's lifetime, Purchase Rights shall
be exercisable only by such Participant.

      (e) Unless otherwise specified in an Offering, the Company shall have no
obligation to pay interest on Contributions.

9. EXERCISE.

      (a) On each Purchase Date during an Offering, each Participant's
accumulated Contributions shall be applied to the purchase of shares of Common
Stock up to the maximum number of shares of Common Stock permitted pursuant to
the terms of the Plan and the applicable Offering, at the purchase price
specified in the Offering. No fractional shares shall be issued upon the
exercise of Purchase Rights unless specifically provided for in the Offering.

      (b) If any amount of accumulated Contributions remains in a Participant's
account after the purchase of shares of Common Stock and such remaining amount
is less than the amount required to purchase one share of Common Stock on the
final Purchase Date of an Offering, then such remaining amount shall be held in
such Participant's account for the

                                       8.
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purchase of shares of Common Stock under the next Offering under the Plan,
unless such Participant withdraws from such next Offering, as provided in
Section 8(b), or is not eligible to participate in such Offering, as provided in
Section 6, in which case such amount shall be distributed to such Participant
after the final Purchase Date, without interest. If the amount of Contributions
remaining in a Participant's account after the purchase of shares of Common
Stock is at least equal to the amount required to purchase one (1) whole share
of Common Stock on the final Purchase Date of the Offering, then such remaining
amount shall be distributed in full to such Participant at the end of the
Offering without interest.

      (c) No Purchase Rights may be exercised to any extent unless the shares of
Common Stock to be issued upon such exercise under the Plan are covered by an
effective registration statement pursuant to the Securities Act and the Plan is
in material compliance with all applicable federal, state, foreign and other
securities and other laws applicable to the Plan. If on a Purchase Date during
any Offering hereunder the shares of Common Stock are not so registered or the
Plan is not in such compliance, no Purchase Rights or any Offering shall be
exercised on such Purchase Date, and the Purchase Date shall be delayed until
the shares of Common Stock are subject to such an effective registration
statement and the Plan is in such compliance, except that the Purchase Date
shall not be delayed more than twelve (12) months and the Purchase Date shall in
no event be more than twenty-seven (27) months from the Offering Date. If, on
the Purchase Date under any Offering hereunder, as delayed to the maximum extent
permissible, the shares of Common Stock are not registered and the Plan is not
in such compliance, no Purchase Rights or any Offering shall be exercised and
all Contributions accumulated during the Offering (reduced to the extent, if
any, such Contributions have been used to acquire shares of Common Stock) shall
be distributed to the Participants without interest.

10. COVENANTS OF THE COMPANY.

      The Company shall seek to obtain from each federal, state, foreign or
other regulatory commission or agency having jurisdiction over the Plan such
authority as may be required to issue and sell shares of Common Stock upon
exercise of the Purchase Rights. If, after commercially reasonable efforts, the
Company is unable to obtain from any such regulatory commission or agency the
authority that counsel for the Company deems necessary for the lawful issuance
and sale of Common Stock under the Plan, the Company shall be relieved from any
liability for failure to issue and sell Common Stock upon exercise of such
Purchase Rights unless and until such authority is obtained.

11. USE OF PROCEEDS FROM SALES OF COMMON STOCK.

      Proceeds from the sale of shares of Common Stock pursuant to Purchase
Rights shall constitute general funds of the Company.

12. RIGHTS AS A STOCKHOLDER.

      A Participant shall not be deemed to be the holder of, or to have any of
the rights of a holder with respect to, shares of Common Stock subject to
Purchase Rights unless and until the Participant's shares of Common Stock
acquired upon exercise of Purchase Rights are recorded in the books of the
Company (or its transfer agent).

                                       9.
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13. DESIGNATION OF BENEFICIARY.

      (a) A Participant may file a written designation of a beneficiary who is
to receive any shares of Common Stock and/or cash, if any, from the
Participant's account under the Plan in the event of such Participant's death
subsequent to the end of an Offering but prior to delivery to the Participant of
such shares of Common Stock or cash. In addition, a Participant may file a
written designation of a beneficiary who is to receive any cash from the
Participant's account under the Plan in the event of such Participant's death
during an Offering. Any such designation shall be on a form provided by or
otherwise acceptable to the Company.

      (b) The Participant may change such designation of beneficiary at any time
by written notice to the Company. In the event of the death of a Participant and
in the absence of a beneficiary validly designated under the Plan who is living
at the time of such Participant's death, the Company shall deliver such shares
of Common Stock and/or cash to the executor or administrator of the estate of
the Participant, or if no such executor or administrator has been appointed (to
the knowledge of the Company), the Company, in its sole discretion, may deliver
such shares of Common Stock and/or cash to the spouse or to any one or more
dependents or relatives of the Participant, or if no spouse, dependent or
relative is known to the Company, then to such other person as the Company may
designate.

14. ADJUSTMENTS UPON CHANGES IN COMMON STOCK; CORPORATE TRANSACTIONS.

      (a) If any change is made in, or other events occur with respect to, the
Common Stock subject to the Plan or subject to any Purchase Right after the
effective date of the Plan set forth in Section 17 without the receipt of
consideration by the Company (through merger, consolidation, reorganization,
recapitalization, reincorporation, stock dividend, dividend in property other
than cash, stock split, liquidating dividend, combination of shares, exchange of
shares, change in corporate structure or other transaction not involving the
receipt of consideration by the Company (each a "CAPITALIZATION ADJUSTMENT")),
the Plan shall be appropriately adjusted in the class(es) and maximum number of
securities subject to the Plan pursuant to Section 4(a), and the outstanding
Purchase Rights shall be appropriately adjusted in the class(es), number of
shares and purchase limits of such outstanding Purchase Rights. The Board shall
make such adjustments, and its determination shall be final, binding and
conclusive. (Notwithstanding the foregoing, the conversion of any convertible
securities of the Company shall not be treated as a transaction "without receipt
of consideration" by the Company.)

      (b) In the event of a Corporate Transaction, then: (i) any surviving
corporation or acquiring corporation (or the surviving or acquiring
corporation's parent company) may assume or continue Purchase Rights outstanding
under the Plan or may substitute similar rights (including a right to acquire
the same consideration paid to the stockholders in the Corporate Transaction)
for those outstanding under the Plan, or (ii) if any surviving or acquiring
corporation (or its parent company) does not assume or continue such Purchase
Rights or does not substitute similar rights for Purchase Rights outstanding
under the Plan, then the Participants' accumulated Contributions shall be used
to purchase shares of Common Stock within ten (10) business days prior to the
Corporate Transaction under the ongoing Offering, and the Participants' Purchase
Rights under the ongoing Offering shall terminate immediately after such
purchase.

                                      10.
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15. AMENDMENT OF THE PLAN.

      (a) The Board at any time, and from time to time, may amend the Plan.
However, except as provided in Section 14(a) relating to Capitalization
Adjustments and except as to amendments solely to benefit the administration of
the Plan, to take account of a change in legislation or to obtain or maintain
favorable tax, exchange control or regulatory treatment for Participants or the
Company or any Related Corporation, no amendment shall be effective unless
approved by the stockholders of the Company to the extent stockholder approval
is necessary for the Plan to satisfy the requirements of Section 423 of the Code
or other applicable laws or regulations.

      (b) It is expressly contemplated that the Board may amend the Plan in any
respect the Board deems necessary or advisable to provide Employees with the
maximum benefits provided or to be provided under the provisions of the Code and
the regulations promulgated thereunder relating to Employee Stock Purchase Plans
and/or to bring the Plan and/or Purchase Rights into compliance therewith.

      (c) The rights and obligations under any Purchase Rights granted before
amendment of the Plan shall not be impaired by any amendment of the Plan except:
(i) with the consent of the person to whom such Purchase Rights were granted, or
(ii) as necessary to comply with any laws or governmental regulations
(including, without limitation, the provisions of the Code and the regulations
promulgated thereunder relating to Employee Stock Purchase Plans).

16. TERMINATION OR SUSPENSION OF THE PLAN.

      (a) The Board may suspend or terminate the Plan at any time. Unless sooner
terminated, the Plan shall terminate at the time that all of the shares of
Common Stock reserved for issuance under the Plan, as increased and/or adjusted
from time to time, have been issued under the terms of the Plan. No Purchase
Rights may be granted under the Plan while the Plan is suspended or after it is
terminated.

      (b) Any benefits, privileges, entitlements and obligations under any
Purchase Rights while the Plan is in effect shall not be impaired by suspension
or termination of the Plan except (i) as expressly provided in the Plan or with
the consent of the person to whom such Purchase Rights were granted, (ii) as
necessary to comply with any laws, regulations or listing requirements, or (iii)
as necessary to ensure that the Plan and/or Purchase Rights comply with the
requirements of Section 423 of the Code. Notwithstanding the foregoing, if the
Company's accountants advise the Company that the accounting treatment of
purchases under the Plan will change or has changed in a manner that the Company
determines is detrimental to its best interests, then the Company may, in its
discretion, take any or all of the following actions: (i) terminate each
Offering hereunder that is then ongoing as of the next Purchase Date (after the
purchase of Common Stock on such Purchase Date) under such Offering; (ii) set a
new Purchase Date for each ongoing Offering and terminate such Offerings after
the purchase of Common Stock on such Purchase Date; (iii) amend the Plan and the
ongoing Offering so that such Offering will no longer have an accounting
treatment that is detrimental to the Company's best interests and (iv) terminate
each ongoing Offering and refund any Contributions (reduced to the

                                      11.
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extent, if any, such Contributions have been used to acquire shares of Common
Stock) without interest to the participants.

17. EFFECTIVE DATE OF PLAN.

      The Plan shall become effective on the IPO Date, but no Purchase Rights
shall be exercised unless and until the Plan has been approved by the
stockholders of the Company, which approval shall be within twelve (12) months
before or after the date the Plan is adopted by the Board.

18. MISCELLANEOUS PROVISIONS.

      (a) The Plan and Offering do not constitute an employment contract.
Nothing in the Plan or in the Offering shall in any way alter the at will nature
of a Participant's employment or be deemed to create in any way whatsoever any
obligation on the part of any Participant to continue in the employ of the
Company or a Related Corporation, or on the part of the Company or a Related
Corporation to continue the employment of a Participant.

      (b) The provisions of the Plan shall be governed by the laws of the State
of Delaware without resort to that state's conflicts of laws rules.

                                      12.