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                                                                       Exhibit 4

2000 EMPLOYEE STOCK PURCHASE PLAN

1. PURPOSE.

               The Bluestone Software, Inc. 2000 Employee Stock Purchase Plan
(the "Plan") is broadly based and intended to encourage and facilitate the
purchase of Shares of the Common Stock of Bluestone Software, Inc. (the
"Company"), by employees of the Company and any Participating Companies, thereby
providing employees with a personal stake in the Company and a long range
inducement to remain in the employ of the Company and Participating Companies.
It is the intention of the Company that the Plan qualify as an "employee stock
purchase plan" within the meaning of Section 423 of the Code.

2. DEFINITIONS.

               (a) "ACCOUNT" means a bookkeeping account established by the
Committee on behalf of a Participant to hold Payroll Deductions.

               (b) "APPROVED LEAVE OF ABSENCE" means a leave of absence that has
been approved by the applicable Participating Company in such a manner as the
Board may determine from time to time.

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

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

               (e) "COMMITTEE" means the Committee appointed pursuant to Section
14 of the Plan.

               (f) "COMPANY" means Bluestone Software, Inc. and any
successor(s).

               (g) "COMPENSATION" means an Employee's cash compensation payable
for services to a Participating Company.

               (h) "ELECTION FORM" means the form acceptable to the Committee
which an Employee shall use to make an election to purchase Shares through
Payroll Deductions pursuant to the Plan.

               (i) "ELIGIBLE EMPLOYEE" means an Employee who meets the
requirements for eligibility under Section 3 of the Plan.

               (j) "EMPLOYEE" means a person who is an employee of a
Participating Company.

               (k) "FAIR MARKET VALUE" means the closing price per Share on the
principal national securities exchange on which the shares are listed or
admitted to trading or, if not listed or traded on any such exchange, on the
National Market System of the National Association of Securities Dealers
Automated Quotation System ("NASDAQ"), or if not listed or traded on any such
exchange or market, the fair market value as reasonably determined by the Board,
which determination shall be conclusive.

               (l) "FIVE PERCENT OWNER" means an Employee who, with respect to a
Participating Company, is described in Section 423(b) of the Code.

               (m) "OFFERING" means an offering of Shares to Eligible Employees
pursuant to the Plan.

               (n) "OFFERING COMMENCEMENT DATE" means the first day of each
January, April, July and October beginning on or after adoption of the Plan
by the Board; provided that the Board may delay the first Offering
Commencement Date after adoption of the Plan until the first day of any month
in the third or fourth calendar quarter in 2000.

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               (o) "OFFERING PERIOD" means the period extending from an Offering
Commencement Date through the following Offering Termination Date.

               (p) "OFFERING TERMINATION DATE" means the last day of each March,
June, September and December following an Offering Commencement Date.

               (q) "OPTION PRICE" means eighty five percent (85%) of the lesser
of: (1) the Fair Market Value per Share on the Offering Commencement Date, or if
such date is not a trading day, then on the next trading day thereafter or (2)
the Fair Market Value per Share on the Offering Termination Date, or if such
date is not a trading day, then on the next trading day thereafter.

               (r) "PARTICIPANT" means an Employee who meets the requirements
for eligibility under Section 3 of the Plan and who has timely delivered an
Election Form to the Committee.

               (s) "PARTICIPATING COMPANY" means, as provided in Schedule A, the
Company and subsidiaries of the Company, within the meaning of Section 424(f) of
the Code, if any, that are approved by the Board from time to time and whose
employees are designated as Employees by the Board.

               (t) "PAYROLL DEDUCTIONS" means amounts withheld from a
Participant's Compensation pursuant to the Plan, as described in Section 5 of
the Plan.

               (u) "PLAN" means Bluestone Software, Inc. 2000 Employee Stock
Purchase Plan, as set forth in this document, and as may be amended from time to
time.

               (v) "PLAN TERMINATION DATE" means the earlier of:

                       (1) The Offering Termination Date for the Offering in
which the maximum number of Shares specified in Section 5 of the Plan have
been issued pursuant to the Plan; or

                       (2) The date as of which the Board chooses to
terminate the Plan as provided in Section 15 of the Plan.

               (w) "SHARES" means shares of Common Stock of the Company.

               (x) "SUCCESSOR-IN-INTEREST" means the Participant's executor or
administrator, or such other person or entity to whom the Participant's rights
under the Plan shall have passed by will or the laws of descent and
distribution.

               (y) "TERMINATION FORM" means the form acceptable to the Committee
which an Employee shall use to withdraw from an Offering pursuant to Section 8
of the Plan.

3. ELIGIBILITY AND PARTICIPATION.

               (a) INITIAL ELIGIBILITY. Except as provided in Section 3(b) of
the Plan, each individual who is an Employee on an Offering Commencement Date
shall be eligible to participate in the Plan.

               (b) INELIGIBILITY. An Employee shall not be eligible to
participate in the Plan if such Employee:

                       (1) Is a Five Percent Owner;

                       (2) Is a temporary Employee; or

                       (3) Is restricted from participating under Section
3(d) of the Plan.

               (c) LEAVE OF ABSENCE. A Participant who goes on an Approved Leave
of Absence before an Offering Termination Date after having filed an Election
Form with respect to such Offering shall continue to be eligible to

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participate in the Plan through the end of such Offering Period. Termination by
the Participating Company of an Employee's Approved Leave of Absence, other than
termination or return to non-temporary employment, shall terminate an Employee's
employment for all purposes of the Plan and shall terminate such Employee's
participation in the Plan and the right to exercise any option. An Approved
Leave of Absence shall be considered active employment for purposes of Section
3(b)(3) of the Plan.

               (d) RESTRICTIONS ON PARTICIPATION. Notwithstanding any provisions
of the Plan to the contrary, no Employee shall be granted an option to
participate in the Plan if:

                             (1) Immediately after the grant, such Employee
would be a Five Percent Owner; or

                             (2) Such option would permit such Employee's rights
to purchase stock under all employee stock purchase plans of the Participating
Companies which meet the requirements of Section 423(b) of the Code to accrue
at a rate which exceeds $25,000 in fair market value (as determined pursuant to
 Section 423(b)(8) of the Code) for each calendar year in which such option is
outstanding.

               (e) COMMENCEMENT OF PARTICIPATION. An Employee who meets the
eligibility requirements of Sections 3(a) and 3(b) of the Plan and whose
participation is not restricted under Section 3(d) of the Plan shall become a
Participant by completing an Election Form and filing it with the Committee
on or before the 15th day of the month immediately preceding the Offering
Commencement Date for the first Offering to which such Election Form applies
or such other date as specified by the Committee. Payroll Deductions for a
Participant shall commence on the applicable Offering Commencement Date when
his or her authorization for Payroll Deductions becomes effective, and shall
end on the Plan Termination Date, unless sooner terminated by the Participant
pursuant to Section 8 of the Plan.

4. SHARES PER OFFERING.

               The Plan shall be implemented by a series of Offerings that shall
terminate on the Plan Termination Date. Offerings shall be made with respect to
Compensation payable for each Offering Period occurring on or after adoption of
the Plan by the Board and ending with the Plan Termination Date. Shares
available for any Offering shall be the difference between the maximum number of
Shares that may be issued under the Plan, as determined pursuant to Section
10(a) of the Plan, for all of the Offerings, less the actual number of Shares
purchased by Participants pursuant to prior Offerings. If the total number of
Shares for which options are exercised on any Offering Termination Date exceeds
the maximum number of Shares available, the Committee shall make a pro rata
allocation of Shares available for delivery and distribution in as nearly a
uniform manner as practicable, and as it shall determine to be fair and
equitable, and the unapplied Account balances shall be returned to Participants
as soon as practicable following the Offering Termination Date.

5. PAYROLL DEDUCTIONS.

               (a) AMOUNT OF PAYROLL DEDUCTIONS. An Eligible Employee who wishes
to participate in the Plan shall file an Election Form with the Committee at
least 15 days before the Offering Commencement Date for the first Offering
for which such Election Form is effective or such other date as specified by
the Committee, on which he or she may elect to have Payroll Deductions of
such amounts designated by the Committee on the Election Form from time to
time made from his or her Compensation on each regular payday during the time
he or she is a Participant in the Plan, provided that the rules established
by the Committee shall be consistent with Section 423(b)(5) of the Code.

               (b) PARTICIPANTS' ACCOUNTS. All Payroll Deductions with respect
to a Participant pursuant to Section 5(a) of the Plan shall be credited to the
Participant's Account under the Plan.

               (c) CHANGES IN PAYROLL DEDUCTIONS. A Participant may discontinue
his or her participation in the Plan as provided in Section 8(a) of the Plan,
but no other change can be made during an Offering, including, but not limited
to, changes in the amount of Payroll Deductions for such Offering. A Participant
may change the amount of Payroll Deductions for subsequent Offerings by giving
written notice of such change to the Committee on or before the 15th day of the
month immediately preceding the Offering Commencement Date for the Offering for
which such change is effective or such other date as specified by the Committee.

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               (d) LEAVE OF ABSENCE. A Participant who goes on an Approved Leave
of Absence before the Offering Termination Date after having filed an Election
Form with respect to such Offering may:

                             (1) Withdraw the balance credited to his or her
Account pursuant to Section 8(b) of the Plan;

                             (2) Discontinue contributions to the Plan but
remain a Participant in the Plan through the Offering Termination Date; or

                             (3) Remain a Participant in the Plan during such
Approved Leave of Absence through the Offering Termination Date and continue
the authorization for the Participating Company to make Payroll Deductions for
each payroll period out of continuing payments to such Participant, if any.

6. GRANTING OF OPTIONS.

               On each Offering Termination Date, each Participant shall be
deemed to have been granted an option to purchase a minimum of one (1) Share and
a maximum number of Shares that shall be a number of whole Shares equal to the
quotient obtained by dividing the balance credited to the Participant's Account
as of the Offering Termination Date, by the Option Price.

7. EXERCISE OF OPTIONS.

               (a) AUTOMATIC EXERCISE. With respect to each Offering, a
Participant's option for the purchase of Shares granted pursuant to Section 6 of
the Plan shall be deemed to have been exercised automatically on the Offering
Termination Date applicable to such Offering.

               (b) FRACTIONAL SHARES AND MINIMUM NUMBER OF SHARES. Fractional
Shares shall not be issued under the Plan. Amounts credited to an Account
remaining after the application of such Account to the exercise of options for a
minimum of one (1) full Share shall be credited to the Participant's Account for
the next succeeding Offering, or, at the Participant's election, returned to the
Participant as soon as practicable following the Offering Termination Date,
without interest.

               (c) TRANSFERABILITY OF OPTION. No option granted to a Participant
pursuant to the Plan shall be transferable other than by will or by the laws of
descent and distribution, and no such option shall be exercisable during the
Participant's lifetime other than by the Participant.

               (d) DELIVERY OF CERTIFICATES FOR SHARES. The Company shall
deliver certificates for Shares acquired on the exercise of options during an
Offering Period as soon as practicable following the Offering Termination Date.

8. WITHDRAWALS.

               (a) WITHDRAWAL OF ACCOUNT. A Participant may elect to withdraw
the balance credited to the Participant's Account by providing a Termination
Form to the Committee at any time before the Offering Termination Date
applicable to any Offering.

               (b) AMOUNT OF WITHDRAWAL. A Participant may withdraw all, but not
less than all, of the amounts credited to the Participant's Account by giving a
Termination Form to the Committee. All amounts credited to such Participant's
Account shall be paid as soon as practicable following the Committee's receipt
of the Participant's Termination Form, and no further Payroll Deductions will be
made with respect to the Participant.

               (c) TERMINATION OF EMPLOYMENT. Upon termination of a
Participant's employment for any reason other than death, including
termination due to disability or continuation of a leave of absence beyond 90
days, all amounts credited to such Participant's Account shall be returned to
the Participant. In the event of a Participant's (1) termination of
employment due to death or (2) death after termination of employment but
before the Participant's Account has been returned, all amounts credited to
such Participant's Account shall be returned, without interest, to the
beneficiary designated by the Participant in accordance with the procedures
specified by the Committee, or if no beneficiary is designated, to the
Participant's Successor-in-Interest without interest.

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               (d) LEAVE OF ABSENCE. A Participant who is on an Approved Leave
of Absence shall, subject to the Participant's election pursuant to Section 5(d)
of the Plan, continue to be a Participant in the Plan until the end of the first
Offering ending after commencement of such Approved Leave of Absence. A
Participant who has been on an Approved Leave of Absence for more than 90 days
shall not be eligible to participate in any Offering that begins on or after the
commencement of such Approved Leave of Absence so long as such leave of absence
continues.

9. INTEREST.

               No interest shall be paid or allowed with respect to amounts paid
into the Plan or credited to any Participant's Account.

10. SHARES.

               (a) MAXIMUM NUMBER OF SHARES. No more than 600,000 Shares may be
issued under the Plan. Such Shares may be unissued shares or treasury shares of
the Company or may be outstanding shares purchased in the open market or
otherwise on behalf of the Plan upon such terms as the Committee may approve for
delivery under the Plan. The number of Shares available for any Offering and all
Offerings shall be adjusted if the number of outstanding Shares of the Company
is increased or reduced by split-up, reclassification, stock dividend or the
like. All Shares issued pursuant to the Plan shall be validly issued, fully paid
and nonassessable.

               (b) PARTICIPANT'S INTEREST IN SHARES. A Participant shall have no
interest in Shares subject to an option until such option has been exercised.

               (c) REGISTRATION OF SHARES. Shares to be delivered to a
Participant under the Plan shall be registered in the name of the Participant.

               (d) RESTRICTIONS ON EXERCISE. The Board may, in its discretion,
require as conditions to the exercise of any option such conditions as it may
deem necessary to assure that the exercise of options is in compliance with
applicable securities laws.

11. EXPENSES.

               The Participating Companies shall pay all fees and expenses
incurred (excluding individual Federal, state, local or other taxes) in
connection with the Plan. No charge or deduction for any such expenses will be
made to a Participant upon the termination of his or her participation under the
Plan or upon the distribution of certificates representing Shares purchased with
his or her contributions.

12. TAXES.

               The Participating Companies shall have the right to withhold from
each Participant's Compensation an amount equal to all Federal, state, city or
other taxes as the Participating Companies shall determine are required to be
withheld by them. In connection with such withholding, the Participating
Companies may make any such arrangements as are consistent with the Plan as it
may deem appropriate, including the right to withhold from Compensation paid to
a Participant other than in connection with the Plan and the right to withdraw
such amount from the amount standing to the credit of the Participant's Account.

13. PLAN AND CONTRIBUTIONS NOT TO AFFECT EMPLOYMENT.

               The Plan shall not confer upon any Eligible Employee any right to
continue in the employ of the Participating Companies.

14. ADMINISTRATION.

               The Plan shall be administered by the Board, which may delegate
responsibility for such administration to a committee of the Board (the
"Committee") or to a third party administrator under Board or Committee
supervision.

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If the Board fails to appoint the Committee, any references in the Plan to the
Committee shall be treated as references to the Board. The Board, or the
Committee, shall have authority to interpret the Plan, to prescribe, amend and
rescind rules and regulations relating to it, to delegate administrative
functions to a third party administrator and to make all other determinations
deemed necessary or advisable in administering the Plan, with or without the
advice of counsel. The determinations of the Board or the Committee on the
matters referred to in this Section 14 shall be conclusive and binding upon all
persons in interest.

15. AMENDMENT AND TERMINATION.

               The Board may terminate the Plan at any time and may amend the
Plan from time to time in any respect; provided, however, that upon any
termination of the Plan, all Shares or Payroll Deductions (to the extent not yet
applied to the purchase of Shares) under the Plan shall be distributed to the
Participants, provided further, that no amendment to the Plan shall affect the
right of a Participant to receive his or her proportionate interest in the
Shares or his or her Payroll Deductions (to the extent not yet applied to the
purchase of Shares) under the Plan, and provided further that the Company may
seek stockholder approval of an amendment to the Plan if such approval is
determined to be required by or advisable under the regulations of the
Securities and Exchange Commission or the Internal Revenue Service, the rules of
any stock exchange or system on which the Shares are listed or other applicable
law or regulation.

16. EFFECTIVE DATE.

               The Plan shall be effective on February 15, 2000 and will be
implemented in the third calendar quarter of 2000. In the event that the Plan is
not approved by the Company's stockholders within one year of the adoption of
the Plan by the Board, the tax treatment of Section 423 of the Code may not
apply with respect to Shares transferred to Participants on the exercise of
options pursuant to Section 7 of the Plan.

17. GOVERNMENT AND OTHER REGULATIONS.

               (a) IN GENERAL. The purchase of Shares under the Plan shall be
subject to all applicable laws, rules and regulations, and to such approvals by
any governmental agencies as may be required.

               (b) SECURITIES LAW. The Committee shall have the power to make
each grant under the Plan subject to such conditions as it deems necessary or
appropriate to comply with the then-existing requirements of the Securities Act
of 1933, as amended, and the Securities Exchange Act of 1934, as amended,
including Rule 16b-3 (or any similar rule) of the Securities and Exchange
Commission.

18. NON-ALIENATION.

               No Participant shall be permitted to assign, alienate, sell,
transfer, pledge or otherwise encumber his or her interest under the Plan prior
to the distribution to him or her of Share certificates. Any attempt at
assignment, alienation, sale, transfer, pledge or other encumbrance shall be
void and of no effect.

19. NOTICES.

               Any notice required or permitted hereunder shall be sufficiently
given only if delivered personally, telecopied, or sent by first class mail,
postage prepaid, and addressed:

               IF TO THE COMPANY:

               Bluestone Software, Inc.
               300 Stevens Drive, 3rd Floor
               Philadelphia, PA 19113

               Attn: Employee Stock Purchase Plan Committee
               Or any other address provided pursuant to written notice.

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               IF TO THE PARTICIPANT:

               At the address on file with the Company from time to time, or to
such other address as either party may hereafter designate in writing by notice
similarly given by one party to the other.

20. SUCCESSORS.

               The Plan shall be binding upon and inure to the benefit of any
successor, successors or assigns of the Company.

21. SEVERABILITY.

               If any part of this Plan shall be determined to be invalid or
void in any respect, such determination shall not affect, impair, invalidate or
nullify the remaining provisions of this Plan which shall continue in full force
and effect.

22. ACCEPTANCE.

               The election by any Eligible Employee to participate in this Plan
constitutes his or her acceptance of the terms of the Plan and his or her
agreement to be bound hereby.

23. APPLICABLE LAW.

               This Plan shall be construed in accordance with the laws of the
state of Delaware, to the extent not preempted by applicable Federal law.