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                                                                    Exhibit 4.4

                          CSS ACQUISITION CORPORATION
                          ---------------------------

                                2000 STOCK PLAN
                                ---------------


1.        Purpose of Plan.
          ---------------

          The Board of Directors of CSS Acquisition Corporation (the "Company")
has established this 2000 Stock Plan (the "Plan") to give certain key employees
of the Company an equity interest in the Company, and thereby, to provide an
incentive to such employees to continue in the service of the Company, and to
further its growth.

2.        Committee.
          ---------

          The Company shall establish a committee to implement this Plan (the
"Committee"). The Committee shall have the power to resolve any dispute or
disagreement arising out of this Plan or the sale or repurchase of any of the
Common Stock allocated to the Recipients hereunder. The Committee may from time
to time impose any conditions on the sale and repurchase of shares of Common
Stock allocated hereunder as it deems necessary or advisable (i) to ensure that
all rights granted under this Plan satisfy the requirements of the Securities
and Exchange Commission's Rule 16b-3 or any successor rule or (ii) to effect a
public offering of the Company's securities. The interpretation and construction
of any provision of this Plan made by the Committee shall be final and
conclusive. If no Committee has been appointed, the entire Board of Directors
(excluding any member of the Board that shall receive shares of Common Stock
pursuant to this Plan) shall constitute the Committee.

3.        Awards.
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          (a)  Upon adoption of this Plan by the Board, the Company shall be
entitled to issue grants of incentive stock options (each an "Option"), subject
to the terms and conditions set forth herein and to such other terms and
conditions consistent with this Plan as the Committee deems appropriate and as
are specified in writing by the Committee to the individual in a grant
instrument or an amendment to the grant instrument (the "Grant Instrument"). The
Committee shall approve the form and provisions of each Grant Instrument.

          (b)  The aggregate total number of shares of common stock of the
Company ("Common Stock") that may be issued or transferred under the Plan is
35,047 shares (as may be adjusted pursuant to Section 15).

          (c)  All employees of the Company, including employees who are
officers or members of the Board, are eligible to participate in the Plan. The
Committee shall select the employees to receive grants of Options and shall
determine the number of shares of Common Stock subject to a particular grant in
such manner as the Committee determines. Persons who receive options under this
Plan shall hereinafter be referred to collectively as "Recipients" and
individually as "Recipients".

4.        Purchase of Options.
          -------------------

          Each Option (a) shall be evidenced by a written agreement (an "Award
Agreement") and shall be subject to the terms and conditions set forth in the
Award Agreement, (b) will have an exercise price per share of Common Stock, as
determined by the Committee, payable in cash upon exercise, (c) will expire ten
years after the date of grant (the "Exercise Term") to the extent not exercised
prior to such date, (d) will be exercisable solely in accordance

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with the Award Agreement, and (e) may not be exercised by any person other than
the Recipient or, in the case of the Recipient's death, in accordance with
Section 12.

5.        Vesting.
          -------

          All Options shall entitle the Recipient to purchase, in whole at any
time or in part from time to time, thirty-three and one-third percent (33 1/3%)
of the total number of shares covered by such Options after the expiration of
one year from the date such Options are granted, an additional thirty-three and
one-third percent (33 1/3%) of the total number of shares covered by the Options
after the second anniversary of the date such Options are granted and the
remainder of the number of shares of Common Stock subject to the Options after
the third anniversary of the date such Options are granted.

6.        [Intentionally Left Blank]
          --------------------------


7.        Repurchase Right.
          ----------------

          If at any time a Recipient ceases to be employed by, or provide
service to, the Company, for any reason, the Company shall have the option to
purchase all the Common Stock issued pursuant to this Plan (including shares of
Common Stock issued upon the exercise of the Options) and any shares of capital
stock issued with respect to such shares held by the Recipient at a price per
share equal to the fair market value of such Shares (as determined in good faith
by the Committee in its sole discretion). If the Company elects to exercise its
purchase rights hereunder, it will provide the holder with written notice of
such election and will consummate the repurchase at the time and place indicated
in such written notice; provided, the time of the consummation of such
repurchase shall not to be less than ten days nor more than ninety days

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after the date such written notice is received by the holder. The purchase price
shall be paid in cash. The repurchase rights of the Company under this Section 7
shall terminate upon the closing of an underwritten public offering pursuant to
an effective registration statement on Form S-1 filed with the Securities and
Exchange Commission (an "IPO").


8.        Right of First Refusal.
          ----------------------

          No Recipient shall sell, exchange, assign, hypothecate, gift, grant a
security interest, pledge or otherwise encumber or enter into any voting trust
or other agreement with respect to voting rights or any other transfer or
disposition of beneficial interest whatsoever (collectively, "Transfer") the
Common Stock without first offering to sell the Common Stock held by such
Recipient to the Company. Prior to a Transfer of any shares of the Common Stock
the person proposing the Transfer shall deliver a written notice (the "Transfer
Notice") describing in reasonable detail the name of the of offeree, the
purchase price requested and all other material terms of the proposed Transfer.
Upon receipt of the Transfer Notice, the Company (or any person designated by
the Company) shall have the right and option (but not the obligation) to
purchase all or any portion of the securities being offered at the price and on
the terms of the proposed Transfer set forth in the Transfer Notice. Within
thirty (30) days after the receipt of the Transfer Notice, the Company shall
notify the transferring party whether or not it desires to purchase any or all
of the offered securities. If the Company desires to purchase any or all of the
offered securities, the closing of the purchase and sale of such securities
shall be held at the place and on the date established by the Company in its
notice to the transferring party in response to the Transfer Notice, which in no
event shall be less than ten (10) nor more than

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ninety (90) days from the date of such notice. In the event the Company elects
not to purchase all of the offered securities, the transferring party may
Transfer the remaining offered securities to the offeree specified in the
Transfer Notice at a price no less than the price specified in the Transfer
Notice and on other terms no more favorable to the transferee(s) than those
terms specified in the Transfer Notice; provided, such Transfer is completed
within ninety (90) days following the last date on which the Company could have
elected to purchase the offered securities. Any such securities not transferred
within such ninety (90) day period shall be subject to the provision of this
Section 8 upon any subsequent Transfer. Any purported Transfer in violation of
this Agreement shall be null and void and of no force and effect. The right of
first refusal set forth in this Section 8 shall terminate upon an IPO.

9.        Escrow.
          ------

          In order to ensure compliance with the obligations under this Plan,
the Company will hold the certificates representing any Shares in escrow until
the later of (i) the expiration of the Restriction Period and (ii) the
termination of the Company's rights under Sections 7 and 8.

10.       Change of Control.
          -----------------

          (a)  As used herein, a "Change of Control" means any of the following:

               (i) The acquisition by any Person (other than a Current Major
Holder) of 50.1% or more of the combined Voting Power of the Company's then
outstanding Voting Securities; provided, however, that for purposes of this
subsection (a), a Person shall not be deemed to have made an acquisition of
Voting Securities if such Person: (1) acquires Voting Securities as a result of
a stock split, stock dividend or other corporate restructuring in which all

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stockholders of the class of such Voting Securities are treated on a pro rata
basis; (2) acquires the Voting Securities directly from the Company; (3) owns
50.1% or more of the combined Voting Power of the Company's then outstanding
Voting Securities solely as a result of the acquisition of Voting Securities by
the Company or any subsidiary which, by reducing the number of Voting Securities
outstanding, increases the proportional number of shares owned by such Person,
(4) is the Company or any corporation or other Person of which a majority of its
voting power or its equity securities or equity interest is owned directly or
indirectly by the Company (a "Controlled Entity"); or (5) acquires Voting
Securities in connection with a "Non-Control Transaction" (as defined in
subsection (ii) below); or

               (ii) a merger, consolidation or reorganization involving the
Company (a "Business Combination"), unless

                    (a)  the stockholders of the Company, immediately before the
  Business Combination, own, directly or indirectly immediately following the
  Business Combination, at least a majority of the combined voting power of the
  outstanding voting securities of the corporation resulting from the Business
  Combination (the "Surviving Corporation") in substantially the same proportion
  as their ownership of the Voting Securities immediately before the Business
  Combination, and
                    (b)  no Person (other than the Company or any Controlled
  Entity, a trustee or other fiduciary holding securities under one or more
  employee benefit plans or arrangements (or any trust forming a part thereof)
  maintained by the

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     Company, the Surviving Corporation or any Controlled Entity, or any Person
     who, immediately prior to the Business Combination, had Beneficial
     Ownership of 50.1% or more of the then outstanding Voting Securities) has
     Beneficial Ownership of 50.1% or more of the combined voting power of the
     Surviving Corporation's then outstanding voting securities (a Business
     Combination satisfying the conditions of clauses (a) and (b) of this
     subsection (ii) shall be referred to as a "Non-Control Transaction"); or

          (iii)   a complete liquidation or dissolution of the Company; or

          (iv)    the sale or other disposition of all or substantially all of
the assets of the Company (other than a transfer to a Controlled Entity).

     (b)  Notwithstanding the foregoing, a Change of Control shall not be deemed
to occur solely because (A) 50.1% or more of the then outstanding Voting
Securities is Beneficially Owned by (x) a trustee or other fiduciary holding
securities under one or more employee benefit plans or arrangements (or any
trust forming a part thereof) maintained by the Company or any Controlled Entity
or (y) any corporation which, immediately prior to its acquisition of such
interest, is owned directly or indirectly by the stockholders of the Company in
the same proportion as their ownership of stock in the Company immediately prior
to such acquisition, or (B) of the IPO or any other sale of securities which is
unanimously approved by the Board of Directors.

     (c)  "Beneficial Owner", "Beneficially Owned" and "Beneficially Owning"
shall have the meanings applicable under Rule 13-d promulgated under the
Exchange Act.

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          (d)  "Current Major Holder" means General Instrument Corporation,
Cablesoft Communications, Inc. or Motorola, Inc., together with any of their
respective affiliates.

          (e)  "Person" means a person within the meaning of sections 13(d) and
14(d) of the Exchange Act.

          (f)  "Voting Power" means the combined voting power of the then
outstanding Voting Securities.

          (g)  "Voting Securities" means, with respect to the Company or any
subsidiary, any securities issued by the Company or such subsidiary,
respectively, which generally entitle the holder thereof to vote for the
election of directors of the Company.

11.       Consequences of a Change of Control.
          -----------------------------------

          In the event of a both (i) a Change of Control and (ii) the employment
of the Recipient is terminated (a) during the period beginning on the effective
date of such Change of Control and ending on the date that is six months after
the effective date of such Change of Control and (b) other than under the
circumstances set forth in Sections 12(a) or 12(b) or voluntarily by the
Recipient, all Options shall become immediately and fully exercisable.

12.       Termination of Employment.
          -------------------------

          (a)  Death, Disability or Retirement.  In the event of the Disability
               -------------------------------
of the Recipient or in the event the employment of the Recipient is terminated
as a result of his death or voluntary retirement after age 65, or after age 55
with Committee consent, the Recipient may at any time within one (1) year after
such Disability or termination of employment, exercise the Option to the extent,
but only to the extent, that the Option or portion thereof was exercisable on

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the date of such Disability or termination of employment. In the event of the
Recipient's death, the Option shall be exercisable, to the extent provided in
the Plan and this Agreement, by the legatee or legatees under his will, or by
his personal representatives or distributees, and such person or persons shall
be substituted for the Recipient.  The term "Disability" means a mental or
physical condition which, in the opinion of the Committee, renders a Recipient
unable or incompetent to carry out the job responsibilities or the duties to
which such Recipient was assigned at the time the disability was incurred, and
which is expected to be permanent or for an indefinite duration.

          (b)  Cause.  If the Recipient's employment is terminated for Cause (as
               -----
defined below), the Option shall cease to be exercisable as of the date of the
Recipient's termination of employment.  For this purpose, the term "Cause" shall
mean a finding by the Committee that the Recipient (i) has breached his or her
employment contract with the Company or a subsidiary, (ii) has engaged in
disloyalty to the Company or a subsidiary, including, without limitation, fraud,
embezzlement, theft, conviction of a felony or proven dishonesty in the course
of his or her employment, (iii) has disclosed trade secrets or confidential
information of the Company or a subsidiary to persons not entitled to receive
such information or (iv) has engaged in other behavior detrimental to the
interest of the Company or a subsidiary as the Committee determines.

          (c)  Other Termination of Employment. If the employment of the
               -------------------------------
Recipient is terminated under any circumstance other than those set forth in
Section 12(a) or 12(b), the Recipient may, at any time within thirty (30) days
after his or her termination of employment,

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exercise the Option to the extent, but only to the extent, that the Option or
portion thereof was exercisable on the date of termination.

          (d)  No Extension of Exercise Term.  Notwithstanding the terms of
               -----------------------------
Section 12(a), 12(b) or 12(c), in no event may the Option be exercised by anyone
after the expiration of the Exercise Term.  Any Option or portion thereof that
was not exercisable on the date of a termination of employment (regardless of
the cause of such termination) shall lapse when the Recipient's employment
terminates (regardless of the cause of such termination).

13.       Transfers.
          ---------

          The Options shall not be Transferred other than by will or the laws of
descent and distribution or pursuant to a domestic relations order.  During the
lifetime of the Recipient, the Option shall be exercisable only by the Recipient
or his or her legal guardian or legal representatives.

14.       Ownership Not to Affect Employment.
          ----------------------------------
          Ownership of Common Stock pursuant to this Plan shall not confer upon
any Recipient any right to continue in the employment of the Company or any of
its subsidiaries.

15.       Adjustments.
          -----------

          (a)  In the event of a reorganization, recapitalization, stock split,
reverse stock split, spin-off, split-off, split up, stock dividend, issuance of
stock rights, combination of shares, merger, consolidation or any other change
in the corporate structure of the Company affecting the Common Stock, or any
distribution to stockholders in respect of stock other than a cash dividend, the
Committee, in its sole discretion, shall make appropriate equitable adjustment
in the number

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and kind of shares authorized by the Plan and any adjustments to outstanding
Options as it determines appropriate. If during the term of any Option granted
hereunder the Company shall be merged into or consolidated with or otherwise
combined with or acquired by a person or entity, or there is a liquidation of
the Company, then at the election of the Committee, in its sole discretion, the
Committee may take such other action as the Committee shall determine to be
reasonable under the circumstances to permit the Recipients to realize the value
of their unexercised Options, including without limitation paying cash to such
Recipient equal to the value of the unexercised Options or requiring an
acquiring corporation to grant options or stock to such Recipient having a value
equal to the value of the unexercised Options.

          (b)  Except as provided by the Committee in accordance with the
foregoing Section 15(a), the Recipients shall have no rights by reason of (i)
any subdivision or consolidation of shares of stock of any class, (ii) the
payment of any dividend or (iii) any other increase or decrease in the number of
shares of stock of any class. Any issuance by the Company of shares of stock of
any class, or securities convertible into shares of stock of any class, shall
not affect, and no adjustment by reason thereof shall be made with respect to,
the number or exercise price of Shares subject to an Option. The grant of an
Option pursuant to the Plan shall not affect in any way the right or power of
the Company to make adjustments, reclassifications, reorganizations or changes
of its capital or business structure, to merge or consolidate or to dissolve,
liquidate, sell or transfer all or any part of its business or assets.

          (c)  All share amounts and per share amounts set forth herein give
effect to a 1-for-3,333 1/3 stock split of the Company's Common Stock to provide
that prior to the

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issuances pursuant to the Plan and by the CSS Acquisition Corporation 2000
Special Stock Incentive Plan, the total issued and outstanding Common Stock of
the Company shall be 1,000,000 shares. Notwithstanding anything to the contrary
contained herein, no adjustment shall be made to the share or per share numbers
set forth herein as a result of such stock split.

16.       Withholding of Taxes.
          --------------------

          (a)  Required Withholding.  All grants of Options and Share Awards
               --------------------
under the Plan shall be subject to applicable tax withholding requirements.  The
Company shall have the right to deduct from all grants and from all wages and
other amounts payable to the Recipient any taxes required by law to be withheld
with respect to grants, or the Company may require that the Recipient or other
person receiving or exercising grants pay to the Company the amount of any taxes
that the Company is required to withhold with respect to such grants.

          (b)  Election to Withhold Shares.  The Committee may require or a
               ---------------------------
Recipient may elect to have the Company's income tax withholding obligation with
respect to a Grant satisfied by having shares withheld up to an amount that does
not exceed the Recipient's applicable withholding tax rate for federal
(including FICA), state and local tax liabilities.  A Recipient's election must
be in a form and manner prescribed by the Committee and shall be subject to the
prior approval of the Committee.

17.       Amendments.
          ----------

          The Board of Directors may from time to time amend the terms of this
Plan as it deems fit; provided, however, that no such amendment shall adversely
                      --------  -------
affect the rights of a holder of the Options issued under the Plan without the
consent of such holder unless the

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Committee deems that such amendment is necessary or advisable to ensure that all
rights granted under this Plan satisfy the requirements of the Securities and
Exchange Commission's Rule 16b-3 or any successor rule.

18.       No Fractional Shares.
          --------------------

          No fractional shares of Company Stock shall be issued or delivered
pursuant to the Plan or any Grant.  The Committee shall determine whether cash,
other awards or other property shall be issued or paid in lieu of such
fractional shares or whether such fractional shares or any rights thereto shall
be forfeited or otherwise eliminated.

19.       Headings.
          --------

          Section headings are for reference only.  In the event of a conflict
between a title and the content of a Section, the content of the Section shall
control.

20.       Compliance With Law.
          -------------------

          The Plan, the exercise of Options and the obligations of the Company
to issue or transfer shares of Common Stock shall be subject to all applicable
laws (including, without limitation federal and state securities laws) and to
approvals by any governmental or regulatory agency as may be required.

21.       No Rights as a Stockholder.
          --------------------------

          A holder of an Option shall have no rights as a stockholder with
respect to any Shares covered by the Option until such person becomes entitled
to receive such Shares by filing a notice of exercise and paying the exercise
price pursuant to the terms of such Option.

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22.       Modification, Extension and Assumption of Options.
          -------------------------------------------------

          Within the limitations of the Plan, the Board of Directors may modify,
extend or assume outstanding Options or may accept the cancellation of
outstanding Options (whether granted by the Company or another issuer) in return
for the grant of new Options for the same or a different number of Shares and at
the same or a different Exercise Price.  The foregoing notwithstanding, no
modification of an Option shall, without the consent of the Recipient, impair
the Recipient's rights or increase the Recipient's obligations under such Option
unless the Committee deems that such modification is necessary or advisable to
ensure that all rights granted under this Plan satisfy the requirements of the
Securities and Exchange Commission's Rule 16b-3 or any successor rule.

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

          The validity, construction, interpretation and effect of the Plan and
the Award Agreements issued under the Plan shall be governed and construed by
and determined in accordance with the laws of the State of Delaware, without
giving effect to the conflict of laws provisions thereof.


Dated as of:  March 15, 2000.

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