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                                                                    EXHIBIT 10.6

                       VOLTERRA SEMICONDUCTOR CORPORATION

                        2004 EMPLOYEE STOCK PURCHASE PLAN

                              ADOPTED: MAY 7, 2004
                       AMENDED AND RESTATED: MAY 17, 2004
                    APPROVED BY STOCKHOLDERS: ________, 2004

1.       PURPOSE.

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

         (c)      "COMMITTEE" means a committee appointed by the Board in
accordance with Section 3(c) of the Plan.

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

         (e)      "COMPANY" means Volterra Semiconductor Corporation, a Delaware
corporation.

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

         (g)      "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:


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

                  (iv)     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.

         (h)      "DILUTED SHARES OUTSTANDING" means, as of any date, (i) the
number of outstanding shares of Common Stock of the Company on such Calculation
Date (as defined in Section 4 herein), plus (ii) the number of shares of Common
Stock issuable upon such Calculation Date assuming the conversion of all
outstanding Preferred Stock and convertible notes, plus (iii) the additional
number of dilutive Common Stock equivalent shares outstanding as the result of
any options or warrants outstanding during the fiscal year, calculated using the
treasury stock method.

         (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. Neither service as a Director nor payment of a director's
fee shall be sufficient to make an individual an Employee of the Company or a
Related Corporation.

         (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 the value of a security, as
determined in good faith by the Board. If the security is listed on any
established stock exchange or traded on the Nasdaq National Market or the Nasdaq
SmallCap Market, the Fair Market Value of the security, unless otherwise
determined by the Board, shall be the closing sales price (rounded up where
necessary to the nearest whole cent) for such security (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 relevant security of the
Company) on the Trading Day prior to the relevant

                                       2.
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determination date, as reported in The Wall Street Journal or such other source
as the Board deems reliable.

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

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

         (q)      "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.

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

         (s)      "PLAN" means this Volterra Semiconductor Corporation 2004
Employee Stock Purchase Plan.

         (t)      "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.

         (u)      "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.

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

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

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

         (y)      "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 to a Committee, as provided in Section 3(c). Whether or
not the Board has delegated administration, the Board shall have the final power
to determine all questions of policy and expediency that may arise in the
administration of the Plan.

         (b)      The Board (or the Committee) 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 the
administration of the Plan. 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 amend the Plan as provided in Section 15.

                  (v)      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 administration of the Plan to a
Committee of the Board composed of one (1) or more members of the Board. 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, 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 abolish the Committee at any time and revest in the Board the
administration of the Plan. If administration is delegated to a Committee,
references to the Board in this Plan and in the Offering document shall
thereafter be deemed to be to the Board or the Committee, as the case may be.

         (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.

         Subject to the provisions of Section 14 relating to adjustments upon
changes in securities, the shares of Common Stock that may be sold pursuant to
Purchase Rights shall not exceed in the aggregate nine hundred thousand
(900,000) shares of Common Stock, plus an annual increase to be added on the
last day of the fiscal year of the Company for a period of ten (10) years,
commencing on the last day of the fiscal year that ends on December 31, 2004 and
ending on (and including) the last day of the fiscal year that ends on December
31, 2013 (each such day, a "Calculation Date"), equal to the lesser of (i) one
and three-quarters percent (1.75%) of the Diluted Shares Outstanding on each
such Calculation Date (rounded down to the nearest whole share) and (ii) two
million (2,000,000) shares of Common Stock. Notwithstanding the foregoing, the
Board may act, prior to the last day of any fiscal year of the Company, to
increase the share reserve by such number of shares of Common Stock as the Board
shall determine, which number shall be less than the amount described in the
prior sentence. If any Purchase Right granted under the Plan shall for any
reason terminate without having been exercised, the

                                       4.
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shares of Common Stock not purchased under such Purchase Right shall again
become available for issuance under the Plan.

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.

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 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/or more than five (5) months per calendar year.

         (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:

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                  (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 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 twenty percent (20%), 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.

                                       6.
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         (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 remain the property of the Participant at all times prior to
the purchase of Common Stock, but such Contributions may be commingled with the
assets of the Company and used for general corporate purposes except where
applicable law requires that Contributions be deposited with an independent
third party. To the extent provided in the Offering, a Participant may begin
making 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

                                       7.
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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
otherwise than by will, the laws of descent and distribution, or 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 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.

         (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 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

                                       8.
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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.

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 shares of Common Stock under the Plan, the Company shall be relieved
from any liability for failure to issue and sell shares of Common Stock upon
exercise of such Purchase Rights unless and until such authority is obtained.

11.      USE OF PROCEEDS FROM SHARES 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).

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

                                       9.
<PAGE>

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 SECURITIES; CORPORATE TRANSACTIONS.

         (a)      If any change is made in the shares of Common Stock, subject
to the Plan, or subject to any Purchase Right, 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), the Plan shall be appropriately
adjusted in the type(s), class(es) and maximum number of shares of Common Stock
subject to the Plan pursuant to Section 4(a), and the outstanding Purchase
Rights shall be appropriately adjusted in the type(s), 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. (The conversion of any convertible securities of the Company shall
not be treated as a "transaction not involving the receipt of consideration by
the Company.")

         (b)      In the event of a Corporate Transaction, then: (i) any
surviving or acquiring corporation (or the surviving or acquiring corporation's
parent company) may continue or assume Purchase Rights outstanding under the
Plan or may substitute similar rights (including a right to acquire the same
consideration paid to 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 continue or assume 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.

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 relating to adjustments upon
changes in securities 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 or to bring the Plan and/or Purchase Rights into compliance therewith.

                                      10.
<PAGE>

         (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 in its discretion 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 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 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 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 as determined by the Board, but no
Purchase Rights shall be exercised unless and until the Plan has been approved
by the stockholders of the Company 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.

                                      11.