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                                                                   EXHIBIT 10.53

                                 SAGETREE, INC.
                    (AS AMENDED EFFECTIVE AS OF MAY 12, 2000)

                            2000 STOCK INCENTIVE PLAN

        SECTION 1. INTRODUCTION. The Board of Directors (the "Board") of
SageTree, Inc., a Delaware corporation (the "Company"), adopted the SageTree,
Inc. 2000 Stock Incentive Plan (this "Plan") on March 28, 2000. This Plan was
approved by the sole stockholder of the Company by written consent dated March
28, 2000. The purpose of this Plan is to promote the long-term success of the
Company and the creation of stockholder value by offering Key Employees an
opportunity to acquire a proprietary interest in the success of the Company, or
to increase such interest, and to encourage such selected persons to continue to
provide services to the Company and to attract new individuals with outstanding
qualifications. This Plan seeks to achieve this purpose by providing for Awards
in the form of Options (which may be Incentive Stock Options or Nonstatutory
Stock Options) and Restricted Stock Awards. This Plan shall be governed by, and
construed in accordance with, the laws of the State of Delaware (except its
choice-of-law provisions).

        SECTION 2. DEFINITIONS. For the purposes of this Plan and any Stock
Option Agreement or Restricted Stock Agreement, the following terms shall have
the meanings indicated (unless otherwise provided in any Stock Option Agreement
or Restricted Stock Agreement):

               (a) "Award" means any Restricted Stock Award or any Option
granted under this Plan.

               (b) "Board" has the meaning set forth in the preamble hereto.

               (c) "Change in Control" means (i) a sale of all or substantially
all of the Company's assets, or (ii) any merger or consolidation of the Company
with or into another corporation if, after the consummation of such transaction,
the holders of the Company's capital stock immediately prior to such transaction
do not hold, immediately following such transaction and by virtue of their
ownership of such shares of capital stock, at least fifty percent (50%) of the
voting power of the surviving corporation or a Parent of such surviving
corporation. A transaction shall not constitute a Change in Control if its sole
purpose is to change the state of the Company's incorporation or to create a
holding company that will be owned in substantially the same proportions by the
persons who held the Company's securities immediately before such transaction.

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


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               (e) "Committee" means a committee consisting of one or more
members of the Board that is appointed by the Board (as described in Section 3)
to administer this Plan.

               (f) Common Stock" means the Company's common stock, par value
$0.001 per share.

               (g) "Company" has the meaning set forth in the preamble hereto.

               (h) "Consultant" means any individual who performs bona fide
services to the Company or a Subsidiary other than as an Employee, a Director or
a Non-Employee Director.

               (i) "Director" means any member of the Board who is also a
common-law employee of the Company, a Subsidiary or a Parent of the Company.

               (j) "Disability" means that the Key Employee is unable to engage
in any substantial gainful activity by reason of any medically determinable
physical or mental impairment which can be expected to result in death or which
has lasted or can be expected to last for a continuous period of not less than
12 months.

               (k) "Employee" means any individual who is a common-law employee
of the Company, a Subsidiary or a Parent of the Company.

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

               (m) "Exercise Price" in the case of an Option, means the amount
for which a Share may be purchased upon exercise of such Option, as specified in
the applicable Stock Option Agreement.

               (n) "Fair Market Value" means the fair market value of a Share,
as determined in good faith by the Committee on such basis as it deems
appropriate.

               (o) "Incentive Stock Option" or "ISO" means an incentive stock
option described in Code section 422(b).

               (p) "Key Employee" means an Employee, a Director, a Non-Employee
Director or a Consultant who has been selected by the Committee to receive an
Award under this Plan.

               (q) "Non-Employee Director" means a member of the Board who is
not a common-law employee of the Company, a Subsidiary or a Parent of the
Company.

               (r) "Nonstatutory Stock Option" or "NSO" means a stock option
that is not an ISO.

               (s) "Option" means an ISO or NSO granted under this Plan.


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               (t) "Parent" of a corporation (the "first corporation") means any
other corporation in an unbroken chain of corporations ending with the first
corporation, if each of the corporations other than the first corporation owns
stock possessing fifty percent (50%) or more of the total combined voting power
of all classes of stock in one of such other corporations in such chain or of
the first corporation.

               (u) "Participant" means an individual or estate who holds an
Award.

               (v) "Plan" has the meaning set forth in the preamble hereto.

               (w) "Restricted Stock" means Common Stock issued or sold to a
Participant under this Plan, other than upon the exercise of an Option.

               (x) "Restricted Stock Agreement" means the agreement between the
Company and the Participant receiving a Restricted Stock Award which contains
the terms, conditions and restrictions pertaining to such Restricted Stock
Award.

               (y) "Restricted Stock Award" means a grant or sale of Restricted
Stock under this Plan.

               (z) "Securities Act" means the Securities Act of 1933, as
amended.

               (aa) "Service" means, unless otherwise provided in any Award,
service as an Employee, Director, Non-Employee Director of, or as a Consultant
to, the Company or any Subsidiary.

               (bb) "Share" means one share of Common Stock.

               (cc) "Stock Option Agreement" means the agreement between the
Company and the Participant receiving an Option that contains the terms,
conditions and restrictions pertaining to such Option.

               (dd) "Subsidiary" means any corporation (other than the Company)
in an unbroken chain of corporations beginning with the Company, if each of the
corporations other than the last corporation in the unbroken chain owns stock
possessing fifty percent (50%) or more of the total combined voting power of all
classes of stock in one of the other corporations in such chain. A corporation
that attains the status of a Subsidiary on a date after the adoption of this
Plan shall be considered a Subsidiary commencing as of such date.

               (ee) "10-Percent Stockholder" means an individual who owns more
than ten percent (10%) of the total combined voting power of all classes of
outstanding stock of the Company, or of any Parent of the Company or any
Subsidiary. In determining stock ownership, the attribution rules of section
424(d) of the Code shall be applied.


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        SECTION 3. ADMINISTRATION.

               (a) Committee Composition. This Plan shall be administered by a
Committee appointed by the Board. The Board shall designate one of the members
of the Committee as chairperson. If no Committee has been appointed, the entire
Board shall constitute the Committee. Members of the Committee shall serve for
such period of time as the Board may determine and shall be subject to removal
by the Board at any time. The Board may also at any time terminate the functions
of the Committee and reassume all powers and authority previously delegated to
the Committee.

               (b) Authority of the Committee. Subject to the provisions of this
Plan, the Committee shall have full authority and discretion to take any actions
it deems necessary or advisable for the administration of this Plan. Such
actions shall include (i) selecting Key Employees who are to receive Awards
under this Plan, (ii) determining the type, number, vesting requirements and
other features and conditions of such Awards, (iii) interpreting this Plan, and
(iv) making all other decisions relating to the operation of this Plan. The
Committee may adopt such rules or guidelines as it deems appropriate to
implement this Plan. The Committee's determinations under this Plan shall be
final and binding on all persons.

               (c) Financial Reports. To the extent required by applicable law,
and not less often than annually, the Company shall furnish to Participants the
Company's summary financial information including a balance sheet regarding the
Company's financial condition and results of operations, unless such
Participants have duties with the Company that assure them access to equivalent
information. Such financial statements need not be audited.

        SECTION 4. ELIGIBILITY. Only Employees, Directors, Non-Employee
Directors and Consultants shall be eligible for designation as Key Employees by
the Committee. Only Key Employees who are common-law employees of the Company or
a Subsidiary or of a Parent of the Company shall be eligible for the grant of
ISOs. An Option may be granted to any Key Employee who is a 10-Percent
Stockholder only if such Option meets the requirements set forth in section
422(c)(5) of the Code.

        SECTION 5. SHARES SUBJECT TO THIS PLAN. The stock issuable under this
Plan shall be authorized but unissued Shares or treasury Shares. The aggregate
number of Shares issued pursuant to this Plan at any time plus the aggregate
number of Shares reserved for Awards under this Plan at such time shall not at
any time exceed 10,600,000 Shares (which number shall be subject to adjustment
as provided in Section 8). If Options are forfeited or if Options terminate for
any other reason before being exercised, then the Shares reserved for issuance
pursuant to such Options shall again become available for Awards under this
Plan. If Shares which were issued as Restricted Stock under this Plan are
repurchased or otherwise reacquired by the Company, then such Shares shall again
become available for Awards under this Plan.


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        SECTION 6. TERMS AND CONDITIONS OF OPTIONS.

               (a) Stock Option Agreement. Each Option granted under this Plan
shall be evidenced by a Stock Option Agreement between the Participant receiving
such Option and the Company. All Options shall be subject to (i) all applicable
terms and conditions of this Plan and (ii) any and all terms and conditions that
are necessary to ensure that the granting of Options under this Plan is exempt
from the qualification or registration requirements of all applicable federal
and state securities laws, rules and regulations. In addition, any Option may be
subject to such other terms and conditions not inconsistent with this Plan that
the Committee deems appropriate for inclusion in a Stock Option Agreement. The
provisions of the various Stock Option Agreements entered into under this Plan
need not be identical. Each Stock Option Agreement shall specify whether the
Option is an ISO or a NSO.

               (b) Number of Shares. Each Stock Option Agreement shall specify
the number of Shares that are subject to the Option and shall provide for the
adjustment of such number in accordance with Section 8. The number of shares
covered by Options granted to any Participant shall not exceed 5,000,000 (which
number shall be subject to adjustment as provided in Section 8).

               (c) Exercise Price. An Option's Exercise Price shall be
established by the Committee and set forth in the Stock Option Agreement
evidencing such Option. To the extent required by law, the Exercise Price of an
ISO shall not be less than 100% of the Fair Market Value (110% for 10-Percent
Stockholders) of a Share on the date of grant. Without limiting the generality
of clause (ii) of the first sentence of Section 6(a), to the extent required to
ensure that the granting of Options under this Plan is exempt from the
qualification or registration requirements of all applicable federal and state
securities laws, rules and regulations, the Exercise Price for an NSO may not be
less than 85% (or such other percentage as may be specified in any such law,
rule or regulation) of the Fair Market Value of a Share on the date of grant,
but otherwise need not be equal to or greater than, or any percentage of, Fair
Market Value on the date of grant. The Exercise Price for a NSO may also vary in
accordance with a predetermined formula.

               (d) Exercisability and Term. Each Stock Option Agreement shall
specify the date when all or any installment of the Option is to become
exercisable. Without limiting the generality of clause (ii) of the first
sentence of Section 6(a), to the extent required to ensure that the granting of
Options under this Plan is exempt from the qualification or registration
requirements of all applicable federal and state securities laws, rules and
regulations, Options shall vest at least at the rate of 20% (or such other
percentage as may be specified in any such law, rule or regulation) annually
over a five-year period, subject to such reasonable conditions as may be
specified in the Stock Option Agreement evidencing such Option. Without limiting
the generality of clause (ii) of the first sentence of Section 6(a), to the
extent a Stock Option Agreement provides for vesting requirements, such
requirements shall be such as to ensure that the granting of Options under this
Plan is exempt from the qualification or registration requirements of all
applicable federal and state securities laws, rules and regulations. Each Stock
Option Agreement shall also specify the term of the Option; provided that the
term of an ISO,


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and to the extent required by applicable law, a NSO, shall in no event exceed
ten (10) years from the date of grant (five (5) years for ISO's granted to
10-Percent Stockholders). Options shall be exercisable for the period or periods
following termination of employment under different circumstances as may be set
forth in the Stock Option Agreement; provided, however, that such period or
periods shall be such as to ensure that the granting of Options under this Plan
is exempt from the qualification or registration requirements of all applicable
federal and state securities laws, rules and regulations. No Option may be
exercised after the expiration date provided in the applicable Stock Option
Agreement. A Stock Option Agreement may provide for accelerated exercisability
upon the occurrence of certain events. A Stock Option Agreement may permit the
Participant holding an Option to exercise such Option before it is vested,
subject to the Company's right to repurchase any Shares acquired under the
unvested portion of the Option (an "early exercise"), which right of repurchase
shall lapse at the same rate the Option would have vested had there been no
early exercise. In no event shall the Company be required to issue fractional
Shares upon the exercise of an Option.

               (e) Effect of a Change in Control. Except as may be otherwise
provided in a particular Stock Option Agreement, in the event of a Change in
Control, each outstanding Option shall be assumed or an equivalent option or
right shall be substituted by the successor corporation or a Parent or a
subsidiary of such successor corporation, unless such successor corporation,
Parent or subsidiary does not agree to assume the outstanding Options, in which
case such Options shall terminate upon the consummation of the transaction. For
purposes of this Section 6(e), an Option shall be considered assumed, without
limitation, if, at the time of issuance of the stock or other consideration upon
a Change in Control, each holder of an Option would be entitled to receive upon
exercise of the Option the same number and kind of shares of stock or the same
amount of property, cash or securities as such holder would have been entitled
to receive upon the occurrence of the transaction if the holder had been,
immediately prior to such transaction, the holder of the number of Shares
covered by the Option at such time (after giving effect to any adjustments in
the number of Shares covered by the Option as provided for in Section 8);
provided however that if such consideration received in the transaction is not
solely common stock of the successor corporation or its Parent, the Committee
may, with the consent of the successor corporation, provide for the
consideration to be received upon exercise of the Option to be solely common
stock of the successor corporation or its Parent equal to the Fair Market Value
of the per Share consideration received by holders of Common Stock in the
transaction.

               (f) Modifications or Assumption of Options. Within the
limitations of this Plan, the Committee may modify, extend or assume outstanding
Options or may accept the cancellation of outstanding options (whether granted
by the Company or by another issuer). The foregoing notwithstanding, no
modification of an Option shall, without the consent of the Participant holding
such Option, alter or impair his or her rights or obligations under such Option.

               (g) Restrictions on Transfer. Any Shares issued upon exercise of
an Option shall be subject to such rights of repurchase, rights of first refusal
and other transfer restrictions as the Committee may determine. Such
restrictions shall apply in addition to any restrictions that


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may apply to holders of Shares generally and shall also comply with any
requirements of any law, rule or regulation to the extent such compliance is
required to ensure that the granting of Options under this Plan is exempt from
the qualification or registration requirements of all applicable federal and
state securities laws, rules and regulations.

               (h) Payment of Exercise Price of Options. The Exercise Price of
any Option shall be payable in cash or as otherwise expressly permitted by the
provisions of the applicable Stock Option Agreement. A Stock Option Agreement
may specify that payment for all or any part of the Exercise Price of any Option
may be made (i) with Shares which have already been owned by the Participant
exercising such Option for at least six months or for such other duration as may
be specified by the Committee (such Shares shall be valued at their Fair Market
Value on the date of exercise), (ii) with a full recourse promissory note or
(iii) in any other form that is consistent with applicable laws, regulations and
rules. The foregoing notwithstanding, the Exercise Price of an Option may be
paid only as expressly provided in the applicable Stock Option Agreement, unless
otherwise expressly authorized by the Committee.

        SECTION 7. TERMS AND CONDITIONS OF RESTRICTED STOCK AWARDS.

               (a) Restricted Stock Awards. Restricted Stock Awards may be
granted by issuing Shares pursuant to the terms of a Restricted Stock Agreement
between the Participant and the Company. Each Restricted Stock Award shall be
subject to (i) all applicable terms and conditions of this Plan and (ii) any and
all terms and conditions that are necessary to ensure that the granting of
Restricted Stock Awards under this Plan is exempt from the qualification or
registration requirements of all applicable federal and state securities laws,
rules and regulations. In addition, any Restricted Stock Award may be subject to
such other terms and conditions not inconsistent with this Plan that the
Committee deems appropriate for inclusion in a Restricted Stock Agreement. The
provisions of the various Restricted Stock Agreements entered into under this
Plan need not be identical. The number of Shares covered by Restricted Stock
Awards granted to any Participant shall not exceed 5,000,000 (which number shall
be subject to adjustment as provided in Section 8).

               (b) Purchase Price. Without limiting the generality of clause
(ii) of the first sentence of Section 7(a), to the extent required to ensure
that the granting of Restricted Stock Awards under this Plan is exempt from the
qualification or registration requirements of all applicable federal and state
securities laws, rules and regulations, the purchase price for Restricted Stock
purchased pursuant to a Restricted Stock Award shall be at least 85% (or such
other percentage as may be specified in any such law, rule or regulation) of the
Fair Market Value of a Share on the date of grant or at the time the purchase is
consummated, or (ii) 100% (or such other percentage as may be specified in any
such law, rule or regulation) of the Fair Market Value of a Share on the date of
grant or at the time the purchase is consummated if the Participant receiving
such Restricted Stock Award is a 10-Percent Stockholder at such time, but
otherwise need not be equal to or greater than, or any percentage of, Fair
Market Value on the date of grant or at the time of purchase.


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               (c) Vesting Conditions. Each Restricted Stock Award shall become
vested, in full or in installments, upon satisfaction of the conditions
specified in the Restricted Stock Agreement. To the extent a Restricted Stock
Award is subject to vesting requirements, such requirements (and the related
repurchase rights with respect to vested and unvested shares) shall be such as
to ensure that the granting of Restricted Stock Awards under this Plan is exempt
from the qualification or registration requirements of all applicable federal
and state securities laws, rules and regulations. A Restricted Stock Agreement
may provide for accelerated vesting upon the occurrence of certain events.
Except as may be otherwise provided in a particular Restricted Stock Agreement,
in the event the shares of Restricted Stock subject to any Restricted Stock
Agreement are converted into any other kind of security or property (including
cash) at any time by virtue of a merger, consolidation or reclassification, such
security or property shall continue to be subject to the vesting and other
restrictions set forth in such Restricted Stock Agreement following such
conversion.

               (d) Voting Rights. The holders of Restricted Stock shall have the
same voting, dividend and other rights as the Company's other stockholders.

        SECTION 8. CERTAIN ADJUSTMENTS. In the event of a subdivision of the
outstanding Shares, a declaration of a dividend payable in Shares, a combination
or consolidation of the outstanding Shares (by reclassification or otherwise)
into a lesser number of Shares, a recapitalization, a spinoff or a similar
occurrence, the Committee shall make such adjustments as it, in its sole
discretion, deems appropriate in one or more of the number and kind of
securities available for future Awards; the number and kind of securities
covered by each outstanding Option; and the Exercise Price of each outstanding
Option. Except as provided in this Section 8 or to the extent a Participant
holds Restricted Stock or Shares issued upon exercise of a Stock Option, a
Participant shall have no rights by reason of any subdivision or consolidation
of shares of stock of any class, or the payment of any stock dividend. In the
event that the Company is a party to a merger or other reorganization,
outstanding Options and shares of Restricted Stock shall be subject to the
agreement of merger or reorganization. Such agreement may provide, without
limitation, for the assumption of outstanding Awards by the surviving
corporation or its Parent or for their continuation by the Company (if the
Company is a surviving corporation), for accelerated vesting and accelerated
expiration, for settlement in cash or for cancellation.

        SECTION 9. LIMITATIONS ON RIGHTS.

               (a) Retention Rights. Neither this Plan nor any Award granted
under this Plan shall be deemed to give any individual a right to remain an
employee, consultant or director of the Company, a Subsidiary or a Parent of the
Company. The Company, each Subsidiary and each Parent of the Company reserve the
right to terminate the service of any person at any time, and for any reason,
subject to applicable laws and any written employment agreement with such
person.

               (b) Stockholders' Rights. A Participant shall have no dividend
rights, voting rights or other rights as a stockholder with respect to any
Shares covered by any Award prior to the issuance of a stock certificate for
such Shares. No adjustment shall be made for cash dividends


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or other rights for which the record date is prior to the date when such
certificate is issued, except as otherwise expressly provided herein.

               (c) Regulatory Requirements. Any other provision of this Plan
notwithstanding, the obligation of the Company to issue Shares under this Plan
shall be subject to all applicable laws, rules and regulations and such approval
by any regulatory body as may be required. The Company reserves the right to
restrict, in whole or in part, the delivery of Shares pursuant to any Award
prior to the satisfaction of all legal requirements relating to the issuance of
such Shares, to their registration, qualification or listing or to an exemption
from registration, qualification or listing.

        SECTION 10. WITHHOLDING TAXES. To the extent required by applicable
federal, state, local or foreign law, a Participant or his or her successor
shall make arrangements satisfactory to the Company for the satisfaction of any
withholding tax obligations that arise in connection with this Plan. The Company
shall not be required to issue any Shares or make any cash payment under this
Plan until such obligations are satisfied. If a public market for the Company's
Shares exists, the Committee may permit a Participant to satisfy all or part of
his or her withholding or income tax obligations by having the Company withhold
all or a portion of any Shares that otherwise would be issued to him or her or
by surrendering all or a portion of any Shares that he or she previously
acquired. Such Shares shall be valued at their Fair Market Value on the date
when taxes otherwise would be withheld in cash. Any payment of taxes by
assigning Shares to the Company may be subject to restrictions, including any
restrictions required by rules of the Securities and Exchange Commission.

        SECTION 11. ASSIGNMENT OR TRANSFER OF AWARDS. Except as provided in
Section 10, or in an applicable agreement, or as required by applicable law, an
Award granted under this Plan shall not be anticipated, assigned, attached,
garnished, optioned, transferred or made subject to any creditor's process,
whether voluntarily, involuntarily or by operation of law; provided, however,
that this Section 11 shall not preclude a Participant from designating a
beneficiary who will receive any outstanding Awards in the event of the
Participant's death, nor shall it preclude a transfer of Awards by will or by
the laws of descent and distribution.. Except as otherwise provided in the
applicable Stock Option Agreement, an Option may be exercised during the
lifetime of the Participant holding such Option only by such Participant or such
Participant's guardian or legal representative. Any act in violation of this
Section 11 shall be void. Except to the extent required to ensure that the
granting of Options and Restricted Stock Awards under this Plan is exempt from
the qualification or registration requirements of all applicable federal and
state securities laws, rules and regulations, neither this Section 11 nor any
other provision of this Plan shall preclude a Participant from transferring or
assigning Shares issued or issuable upon exercise of an Option or shares of
Restricted Stock to (a) the trustee of a trust that is revocable by such
Participant alone, both at the time of the transfer or assignment and at all
times thereafter prior to such Participant's death, or (b) the trustee of any
other trust to the extent approved in advance by the Committee in writing,
provided that a further transfer or assignment from such trustee to any person
other than such Participant shall be permitted only to the extent approved in
advance by the Committee in writing, and Shares held by such trustee


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shall be subject to all of the conditions and restrictions set forth in this
Plan and in the applicable Award, as if such trustee were a party to such Award.

        SECTION 12. DURATION AND AMENDMENTS. This Plan, as set forth herein,
became effective on March 28, 2000, the date on which this Plan was adopted and
approved by the Board and the sole stockholder of the Company. This Plan shall
terminate on March 28, 2010 unless terminated prior to such date as provided in
this Section 12. The Board may amend or terminate this Plan at any time and for
any reason. The termination of this Plan, or any amendment thereof, shall not
affect any Award previously granted under this Plan. No Awards shall be granted
under this Plan after this Plan's termination. An amendment of this Plan shall
be subject to the approval of the Company's stockholder(s) only to the extent
required by any applicable laws, rules or regulations.


        To record the amendment of this Plan effective as of May 12, 2000, the
Company has caused this Plan to be executed by the undersigned officer of the
Company.


                                     SAGETREE, INC.

                                     By:         /s/ Gerald L. Hill
                                        ----------------------------------
                                     Title:     Founder & Interim CEO
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