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                                                                    Exhibit 10.3

                                MAINSPRING, INC.

                        2000 EMPLOYEE STOCK PURCHASE PLAN

Article 1 - Purpose.
-------------------

         This 2000 Employee Stock Purchase Plan (the "Plan") is intended to
encourage stock ownership by all eligible employees of Mainspring, Inc. (the
"Company"), a Delaware corporation, and its participating subsidiaries (as
defined in Article 17) so that they may share in the growth of the Company by
acquiring or increasing their proprietary interest in the Company. This Plan is
designed to encourage eligible employees to remain in the employ of the Company
and its participating subsidiaries. This Plan is intended to constitute an
"employee stock purchase plan" within the meaning of Section 423(b) of the
Internal Revenue Code of 1986, as amended (the "Code").

Article 2 - Administration of the Plan.
--------------------------------------

         This Plan may be administered by a committee appointed by the Board of
Directors of the Company (the "Committee"). The Committee shall consist of not
less than two members of the Company's Board of Directors. The Board of
Directors may from time to time remove members from, or add members to, the
Committee. Vacancies on the Committee, howsoever caused, shall be filled by the
Board of Directors. The Committee may select one of its members as Chairman, and
shall hold meetings at such times and places as it may determine. Acts by a
majority of the Committee, or acts reduced to or approved in writing by a
majority of the members of the Committee, shall be the valid acts of the
Committee.

         The interpretation and construction by the Committee of any provisions
of this Plan or of any option granted under it, shall be final, unless otherwise
determined by the Board of Directors. The Committee may from time to time adopt
such rules and regulations for carrying out this Plan as it may deem best,
provided that any such rules and regulations shall be applied on a uniform basis
to all employees under the Plan. No member of the Board of Directors or the
Committee shall be liable for any action or determination made in good faith
with respect to this Plan or any option granted under it.

         In the event the Board of Directors fails to appoint or refrains from
appointing a Committee, the Board of Directors shall have all power and
authority to administer this Plan. In such event, the word "Committee" wherever
used herein shall be deemed to mean the Board of Directors. The Compensation
Committee of the Board of Directors may also administer this Plan.

Article 3 - Eligible Employees.
------------------------------

         All employees of the Company or any of its participating subsidiaries
whose customary employment is more than twenty (20) hours per week and for more
than five (5) months in any
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                                      -2-

calendar year shall be eligible to receive options under this Plan to purchase
common stock of the Company, and all eligible employees shall have the same
rights and privileges hereunder. Persons who are eligible employees on the first
business day of any Offering Period (as defined in Article 5) shall receive
their options as of such day. Persons who become eligible employees after any
date on which options are granted under this Plan shall be granted options on
the first day of the next succeeding Offering Period on which options are
granted to eligible employees under this Plan. Directors who are not employees
of the Company shall not be eligible to receive options under the Plan. In no
event, however, may an employee be granted an option if such employee,
immediately after the option was granted, would be treated as owning 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 parent corporation or
subsidiary corporation, as the terms "parent corporation" and "subsidiary
corporation" are defined in Section 424(e) and (f) of the Code. For purposes of
determining stock ownership under this paragraph, the rules of Section 424(d) of
the Code shall apply, and stock which the employee may purchase under
outstanding options shall be treated as stock owned by the employee.

Article 4 - Stock Subject to the Plan.
-------------------------------------

         The stock subject to the options under this Plan shall be shares of the
Company's authorized but unissued Common Stock, par value $.01 per share (the
"Common Stock"), or shares of Common Stock reacquired by the Company, including
shares purchased in the open market. The aggregate number of shares which may be
issued pursuant to this Plan is 1,000,000 shares, which number shall
automatically increase on January 1 of each year, beginning January 1, 2001, by
such number of shares as is equal to the lesser of (i) 2% of the total number of
shares of Common Stock outstanding on December 31 of the prior year and (ii)
1,000,000 shares. The number of shares which may be issued under this Plan shall
at all times be subject to adjustment as provided in Article 12. If any option
granted under this Plan shall expire or terminate for any reason without having
been exercised in full or shall cease for any reason to be exercisable in whole
or in part, the unpurchased shares subject thereto shall again be available
under this Plan.

Article 5 - Effectiveness; Payment Period and Stock Options.
-----------------------------------------------------------

         Offering Periods during which payroll deductions will be accumulated
under this Plan shall consist of twenty-four month overlapping periods
commencing every six months on May 1st and November 1st of each calendar year
(each an "Offering Period); provided, however, that the First Offering Period
shall commence immediately upon the effectiveness of the Registration Statement
on Form S-1 filed in connection with the initial public offering of the
Company's Common Stock (the "Initial Public Offering"), and shall end on April
30, 2002 (the "First Offering Period").

         Each Offering Period, with the exception of the First Offering Period,
shall be comprised of four consecutive six-month Payment Periods (each a
"Payment Period"); provided, however, that the first Payment Period in the First
Offering Period shall commence on the first day of the First Offering Period and
end on October 31, 2000.The second Payment Period of the First Offering Period
shall commence on November 1, 2000, and shall end on April 30, 2001. The
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                                      -3-

third Payment Period of the First Offering Period shall commence on May 1, 2001,
and shall end on October 31, 2001. The fourth and final Payment Period of the
First Offering Period shall commence on November 1, 2001 and shall end on April
30, 2002. The Committee shall have the power to change the duration of Offering
Periods and/or Payment Periods (including the commencement dates thereof) with
respect to future offerings without shareholder approval if such change is
announced at least five days prior to the scheduled beginning of the first
Offering Period to be affected thereafter.

         On the first business day of each Offering Period, the Company will
grant to each eligible employee who is then a participant in this Plan an option
to purchase on the last day of each Payment Period within such Offering Period,
at the Option Price hereinafter provided for, a maximum of one thousand (1,000)
shares per Payment Period, on condition that such employee remains eligible to
participate in this Plan throughout the remainder of such Payment Period. The
participant shall be entitled to exercise the option so granted only to the
extent of the participant's accumulated payroll deductions on the last day of
such Payment Period. If the participant's accumulated payroll deductions on the
last day of the Payment Period would enable the participant to purchase more
than 1,000 shares except for the 1,000-share limitation, the excess of the
amount of the accumulated payroll deductions over the aggregate purchase price
of the 1,000 shares shall be promptly refunded to the participant by the
Company, without interest. The option price per share for each Payment Period
shall be the lesser of (i) 85% of the average market price of the Common Stock
on the first business day of the Offering Period to which such Payment Period
relates, and (ii) 85% of the average market price of the Common Stock on the
last business day of such Payment Period, in either event rounded up to avoid
fractions of a dollar other than 1/4, 1/2 and 3/4 (the "Option Price"). The
foregoing limitation on the number of shares subject to options and the Option
Price shall be subject to adjustment as provided in Article 12.

         For purposes of this Plan, the term "average market price" on any date
means (i) the average (on that date) of the high and low prices of the Common
Stock on the principal national securities exchange on which the Common Stock is
traded, if the Common Stock is then traded on a national securities exchange; or
(ii) the last reported sale price (on that date) of the Common Stock on the
Nasdaq Market, if the Common Stock is not then traded on a national securities
exchange; or (iii) the average of the closing bid and asked prices last quoted
(on that date) by an established quotation service for over-the-counter
securities, if the Common Stock is not reported on the Nasdaq Market; or (iv) if
the Common Stock is not publicly traded, the fair market value of the Common
Stock as determined by the Committee after taking into consideration all factors
which it deems appropriate, including, without limitation, recent sale and offer
prices of the Common Stock in private transactions negotiated at arm's length.
Notwithstanding the foregoing, the average market price of Common Stock on the
first business of the First Offering Period shall equal the price per share at
which the Common Stock is sold to the underwriters upon the Initial Public
Offering, without regard to any applicable discounts or commissions provided to
such underwriters. For purposes of determining the "last reported" sale price or
the "last quoted" price for the foregoing provision, the last reported or quoted
prices shall mean, as the case may be, at 4:00 p.m., New York time, on that day.
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                                      -4-

         For purposes of this Plan, the term "business day" means a day on which
there is trading on the Nasdaq Market or the aforementioned national securities
exchange, whichever is applicable pursuant to the preceding paragraph; and if
neither is applicable, a day that is not a Saturday, Sunday or legal holiday in
the Commonwealth of Massachusetts.

         No employee shall be granted an option which permits the employee's
right to purchase stock under this Plan, and under all other Section 423(b)
employee stock purchase plans of the Company and any parent or subsidiary
corporations, to accrue at a rate which exceeds $25,000 of fair market value of
such stock (determined on the date or dates that options on such stock were
granted) for each calendar year in which such option is outstanding at any time.
The purpose of the limitation in the preceding sentence is to comply with
Section 423(b)(8) of the Code. If the participant's accumulated payroll
deductions on the last day of the Payment Period would otherwise enable the
participant to purchase Common Stock in excess of the Section 423(b)(8)
limitation described in this paragraph, the excess of the amount of the
accumulated payroll deductions over the aggregate purchase price of the shares
actually purchased shall be promptly refunded to the participant by the Company,
without interest.

Article 6 - Exercise of Option.
------------------------------

         Each eligible employee who continues to be a participant in this Plan
on the last day of a Payment Period shall be deemed to have exercised his or her
option on such date and shall be deemed to have purchased from the Company such
number of full shares of Common Stock reserved for the purpose of this Plan as
the participant's accumulated payroll deductions on such date will pay for at
the Option Price, subject to the 1,000-share limit of the option and the Section
423(b)(8) limitation described in Article 5. If the individual is not a
participant on the last day of a Payment Period, then he or she shall not be
entitled to exercise his or her option and the amount of his or her payroll
deduction shall be refundable. Only full shares of Common Stock may be purchased
under this Plan. Unused payroll deductions remaining in a participant's account
at the end of a Payment Period by reason of the inability to purchase a
fractional share shall be carried forward to the next Payment Period.

Article 7 - Authorization for Entering the Plan.
-----------------------------------------------

         An employee may elect to enter this Plan by filling out, signing and
delivering to the Company an authorization:

            A.   Stating the percentage to be deducted regularly from the
         employee's pay;

            B.   Authorizing the purchase of stock for the employee in each
         Payment Period in accordance with the terms of this Plan; and

            C.   Specifying the exact name or names in which stock purchased for
         the employee is to be issued as provided under Article 11 hereof.
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                                      -5-

         Such authorization must be received by the Company at least ten (10)
business days before the first day of the next succeeding Offering Period and
shall take effect only if the employee is an eligible employee on the first
business day of such Offering Period; provided, however, that authorizations
relating to the First Offering Period may be received up to 10 days after the
Initial Public Offering and subsequent payroll deductions shall be calculated as
if such authorization was effective as of the Initial Public Offering.

         Unless a participant files a new authorization or withdraws from this
Plan, the deductions and purchases under the authorization the participant has
on file under this Plan will continue from one Offering Period to succeeding
(but not overlapping) Offering Periods as long as this Plan remains in effect.
Notwithstanding any of the foregoing, if the average market price of the Common
Stock on the last business day of a Payment Period is lower than the average
market price of the Common Stock on the first business day of the Offering
Period to which such Payment Period relates, then on the last business day of
such Payment Period all participants shall be automatically withdrawn from such
Offering Period and automatically re-enrolled in the immediately following
Offering Period as of the first day thereof. Eligible employees may not
participate in more than one Offering Period at a time.

         The Company will accumulate and hold for each participant's account the
amounts deducted from his or her pay. No interest will be paid on these amounts.

Article 8 - Maximum Amount of Payroll Deductions.
------------------------------------------------

         An employee may authorize payroll deductions in an amount (expressed as
a whole percentage) not less than one percent (1%) but not more than twenty
percent (20%) of the employee's total compensation including base pay or salary
and any overtime, bonuses and commissions.

Article 9 - Change in Payroll Deductions.
----------------------------------------

         Deductions may not be increased or decreased during an Offering Period.
However, a participant may withdraw in full from an Offering Period.

Article 10 - Withdrawal from the Plan.
-------------------------------------

         A participant may withdraw from the Plan (in whole but not in part) at
any time prior to the last day of a Payment Period by delivering a withdrawal
notice to the Company, in which event the Company will promptly refund the
entire balance of the employee's deductions not previously used to purchase
stock under such Payment Period.

         To re-enter this Plan, an employee who has previously withdrawn must
file a new authorization at least ten (10) business days before the first day of
the next Offering Period in which he or she wishes to participate. The
employee's re-entry into this Plan becomes effective at the beginning of such
Offering Period, provided that he or she is an eligible employee on the first
business day of the Offering Period.
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                                      -6-


Article 11 - Issuance of Stock.
------------------------------

         Certificates for stock issued to participants shall be delivered as
soon as practicable after each Payment Period by the Company's transfer agent.

         Stock purchased under this Plan shall be issued only in the name of the
participant, or if the participant's authorization so specifies, in the name of
the participant and another person of legal age as joint tenants with rights of
survivorship.

Article 12 - Adjustments.
------------------------

         Upon the happening of any of the following described events, a
participant's rights to options granted under this Plan shall be adjusted as
hereinafter provided:

                A.   In the event that the shares of Common Stock shall be
         subdivided or combined into a greater or smaller number of shares or
         if, upon a reorganization, split-up, liquidation, recapitalization or
         the like of the Company, the shares of Common Stock shall be exchanged
         for other securities of the Company, each participant shall be
         entitled, subject to the conditions herein stated, to purchase such
         number of shares of Common Stock or amount of other securities of the
         Company as were exchangeable for the number of shares of Common Stock
         that such participant would have been entitled to purchase except for
         such action, and appropriate adjustments shall be made in the purchase
         price per share to reflect such subdivision, combination or exchange;
         and

                B.   In the event the Company shall issue any of its shares as a
         stock dividend upon, or with respect to, the shares of stock of the
         class which shall at the time be subject to options hereunder, each
         participant upon exercising such an option shall be entitled to receive
         (for the purchase price paid upon such exercise) the shares as to which
         the participant is exercising his or her option and, in addition
         thereto (at no additional cost), such number of shares of the class or
         classes in which such stock dividend or dividends were declared or
         paid, and such amount of cash in lieu of fractional shares, as is equal
         to the number of shares thereof and the amount of cash in lieu of
         fractional shares, respectively, which the participant would have
         received if the participant had been the holder of the shares as to
         which the participant is exercising his or her option at all times
         between the date of the granting of such option and the date of its
         exercise.

         Upon the happening of any of the foregoing events, the class and
aggregate number of shares set forth in Article 4 hereof which are subject to
options which have been or may be granted under this Plan and the limitations
set forth in the second paragraph of Article 5 shall also be appropriately
adjusted to reflect the events specified in paragraphs A and B above.
Notwithstanding the foregoing, any adjustments made pursuant to paragraphs A or
B shall be made only after the Committee, based on advice of counsel for the
Company, determines whether such adjustments would constitute a "modification"
(as that term is defined in Section 424 of the
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                                      -7-

Code). If the Committee determines that such adjustments would constitute a
modification, it may refrain from making such adjustments.

         If the Company is to be consolidated with or acquired by another entity
in a merger, a sale of all or substantially all of the Company's assets or
otherwise (an "Acquisition"), the Committee or the board of directors of any
entity assuming the obligations of the Company hereunder (the "Successor Board")
shall, with respect to options then outstanding under this Plan, either (i) make
appropriate provision for the continuation of such options by arranging for the
substitution on an equitable basis for the shares then subject to such options
either (a) the consideration payable with respect to the outstanding shares of
the Common Stock in connection with the Acquisition, (b) shares of stock of the
successor corporation, or a parent or subsidiary of such corporation, or (c)
such other securities as the Successor Board deems appropriate, the fair market
value of which shall not materially exceed the fair market value of the shares
of Common Stock subject to such options immediately preceding the Acquisition;
(ii) terminate each participant's options in exchange for a cash payment equal
to the excess of (a) the fair market value on the date of the Acquisition of the
number of shares of Common Stock that the participant's accumulated payroll
deductions as of the date of the Acquisition could purchase, at an option price
determined with reference only to the first business day of the applicable
Payment Period and subject to the 1,000-share, Code Section 423(b)(8) and
fractional-share limitations on the amount of stock a participant would be
entitled to purchase, over (b) the result of multiplying such number of shares
by such option price; or (iii) provide for the assumption of the purchase rights
by such acquiring party, subject to the same terms and conditions set forth
herein, except that any purchase price shall be adjusted to reflect any exchange
ratio.

         The Committee or Successor Board shall determine the adjustments to be
made under this Article 12, and its determination shall be conclusive.

Article 13 - No Transfer or Assignment of Employee's Rights.
-----------------------------------------------------------

         An employee's rights under this Plan are the employee's alone and may
not be transferred or assigned to, or availed of by, any other person other than
by will or the laws of descent and distribution. Any option granted under this
Plan to an employee may be exercised, during the employee's lifetime, only by
the employee.

Article 14 - Termination of Employee's Rights.
---------------------------------------------

         Whenever a participant ceases to be an eligible employee because of
retirement, voluntary or involuntary termination, resignation, layoff,
discharge, death or for any other reason, his or her rights under this Plan
shall immediately terminate, and the Company shall promptly refund, without
interest, the entire balance of his or her payroll deduction account under this
Plan. Notwithstanding the foregoing, eligible employment shall be treated as
continuing intact while a participant is on military leave, sick leave or other
bona fide leave of absence, for up to 90 days, or, if longer than 90 days, for
so long as the participant's right to re-employment is guaranteed either by
statute or by contract.
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                                      -8-


         If a participant's payroll deductions are interrupted by any legal
process, a withdrawal notice will be considered as having been received from the
participant on the day the interruption occurs.

Article 15 - Termination and Amendments to Plan.
-----------------------------------------------

         Unless terminated sooner as provided below, this Plan shall terminate
on December 31, 2010. This Plan may be terminated at any time by the Company's
Board of Directors but such termination shall not affect options then
outstanding under this Plan. It will terminate in any case when all or
substantially all of the unissued shares of stock reserved for the purposes of
this Plan have been purchased. If at any time shares of stock reserved for the
purpose of this Plan remain available for purchase but not in sufficient number
to satisfy all then unfilled purchase requirements, the available shares shall
be apportioned among participants in proportion to the amount of payroll
deductions accumulated on behalf of each participant that would otherwise be
used to purchase stock, and this Plan shall terminate. Upon such termination or
any other termination of this Plan, all payroll deductions not used to purchase
stock will be refunded, without interest.

         The Committee or the Board of Directors may from time to time adopt
amendments to this Plan provided that, without the approval of the stockholders
of the Company, no amendment may (i) increase the number of shares that may be
issued under this Plan (except as provided in Article 4); (ii) change the class
of employees eligible to receive options under this Plan, if such action would
be treated as the adoption of a new plan for purposes of Section 423(b) of the
Code; or (iii) cause Rule 16b-3 under the Securities Exchange Act of 1934 to
become inapplicable to this Plan.

Article 16 - Limits on Sale of Stock Purchased under the Plan.
-------------------------------------------------------------

         This Plan is intended to provide shares of Common Stock for investment
and not for resale. The Company does not, however, intend to restrict or
influence any employee in the conduct of his or her own affairs. An employee
may, therefore, sell stock purchased under this Plan at any time the employee
chooses, subject to compliance with any applicable Federal or state securities
laws and subject to any restrictions imposed under Article 21 to ensure that tax
withholding obligations are satisfied. THE EMPLOYEE ASSUMES THE RISK OF ANY
MARKET FLUCTUATIONS IN THE PRICE OF THE STOCK.

Article 17 - Participating Subsidiaries.
---------------------------------------

         The term "participating subsidiary" shall mean any present or future
subsidiary of the Company, as that term is defined in Section 424(f) of the
Code, which is designated from time to time by the Board of Directors to
participate in this Plan. The Board of Directors shall have the power to make
such designation before or after this Plan is approved by the stockholders.
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                                      -9-


Article 18 - Optionees Not Stockholders.
---------------------------------------

         Neither the granting of an option to an employee nor the deductions
from his or her pay shall constitute such employee a stockholder of the shares
covered by an option until such shares have been actually purchased by the
employee.

Article 19 - Application of Funds.
---------------------------------

         The proceeds received by the Company from the sale of Common Stock
pursuant to options granted under this Plan will be used for general corporate
purposes.

Article 20 - Notice to Company of Disqualifying Disposition.
-----------------------------------------------------------

         By electing to participate in this Plan, each participant agrees to
notify the Company in writing immediately after the participant transfers Common
Stock acquired under this Plan, if such transfer occurs within two years after
the first business day of the Payment Period in which such Common Stock was
acquired. Each participant further agrees to provide any information about such
a transfer as may be requested by the Company or any subsidiary corporation in
order to assist it in complying with the tax laws. Such dispositions generally
are treated as "disqualifying dispositions" under Sections 421 and 424 of the
Code, which have certain tax consequences to participants and to the Company and
its participating subsidiaries.

Article 21 - Withholding of Additional Income Taxes.
---------------------------------------------------

         By electing to participate in this Plan, each participant acknowledges
that the Company and its participating subsidiaries are required to withhold
taxes with respect to the amounts deducted from the participant's compensation
and accumulated for the benefit of the participant under this Plan, and each
participant agrees that the Company and its participating subsidiaries may
deduct additional amounts from the participant's compensation, when amounts are
added to the participant's account, used to purchase Common Stock or refunded,
in order to satisfy such withholding obligations. Each participant further
acknowledges that when Common Stock is purchased under this Plan the Company and
its participating subsidiaries may be required to withhold taxes with respect to
all or a portion of the difference between the fair market value of the Common
Stock purchased and its purchase price, and each participant agrees that such
taxes may be withheld from compensation otherwise payable to such participant.
It is intended that tax withholding will be accomplished in such a manner that
the full amount of payroll deductions elected by the participant under Article 7
will be used to purchase Common Stock. However, if amounts sufficient to satisfy
applicable tax withholding obligations have not been withheld from compensation
otherwise payable to any participant, then, notwithstanding any other provision
of this Plan, the Company may withhold such taxes from the participant's
accumulated payroll deductions and apply the net amount to the purchase of
Common Stock, unless the participant pays to the Company, prior to the exercise
date, an amount sufficient to satisfy such withholding obligations. Each
participant further acknowledges that the Company and its participating
subsidiaries may be required to withhold taxes in connection with the
disposition of stock acquired under this Plan and agrees that the Company or any
participating subsidiary may take
<PAGE>

                                     -10-


whatever action it considers appropriate to satisfy such withholding
requirements, including deducting from compensation otherwise payable to such
participant an amount sufficient to satisfy such withholding requirements or
conditioning any disposition of Common Stock by the participant upon the payment
to the Company or such subsidiary of an amount sufficient to satisfy such
withholding requirements.

Article 22 - Governmental Regulations.
-------------------------------------

         The Company's obligation to sell and deliver shares of Common Stock
under this Plan is subject to the approval of any governmental authority
required in connection with the authorization, issuance or sale of such shares.

         Government regulations may impose reporting or other obligations on the
Company with respect to this Plan. For example, the Company may be required to
identify shares of Common Stock issued under this Plan on its stock ownership
records and send tax information statements to employees and former employees
who transfer title to such shares.

Article 23 - Governing Law.
--------------------------

         The validity and construction of this Plan shall be governed by the
laws of the State of Delaware, without giving effect to the principles of
conflicts of law thereof.





Adopted by the Board of Directors on:
February 9, 2000

Adopted by the Stockholders on:
March 29, 2000