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                                                                   EXHIBIT 10.99


July 18, 2002



Dear Masood:

This letter confirms our agreement around the changes in your employment with
Sun Microsystems, Inc. For ease of reference, this letter will be referred to
here and in other documents as the "Transition Agreement."

1.  Beginning May 1, 2003, you will move to part time status with a
    corresponding reduction in your salary to fifty percent of your current base
    salary. You will continue to provide services to Sun such as participating
    in Sun's Leadership Institute, leading or participating in Sun customer
    visits, consulting to internal Sun organizations, and other assignments as
    deemed necessary and appropriate by Sun's Chairman and CEO. You will
    nominally report to Sun's Chairman and CEO. As a practical matter your
    liaison for administrative issues such as work balance and recording, travel
    expense reports, etc, will be Crawford Beveridge.

2.  Beginning May 1, 2003, all stock option vesting will cease and the unvested
    portion of your Sun options will be canceled. This is a change from your
    current stock option agreements. This will not have an impact on the
    unexercised portion of your vested options.

3.  You hereby waive participation in Sun's FY03 Officer and Director Bonus
    Plan, Executive Management Group.

4.  For the period from May l, 2003 through December 31, 2003 you will continue
    to receive coverage under Sun's flexible benefits policies.

5.  On December 31, 2003, you will retire from Sun and will be eligible for the
    benefits outlined in the attached document, "When you Retire from Sun." As
    we've discussed, you will use all accrued vacation prior to May 1, 2003, and
    any vacation payout upon your retirement will only be for vacation accrued
    from May 1, 2003 through December 31, 2003.

6.  You will be subject to the Employee Proprietary Information Agreement you
    signed at hire, as well as the policies applicable to employees generally,
    including Sun's Standards of Business Conduct. Both the Employee Proprietary
    Information Agreement and the Standards of Business Conduct prohibit
    employees from engaging in other employment which constitutes a conflict of
    interest with their employment at the Company. To avoid such a conflict, in
    the event you desire to work elsewhere in any capacity prior to your
    termination date, whether as an employee, contractor or consultant, you must
    notify me and obtain my written consent in advance of commencement of any
    such work. Any such outside work, if approved, can be for no more than
    half-time status. Should you commence such outside work without advance
    disclosure and my consent, or if you perform such outside work on more than
    half-time status, you will be considered as having voluntarily terminated
    your employment effective on the date such work commences. In such case this
    agreement will be


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    null and void as of such date and Sun will have no obligation to provide or
    allow the things mentioned in this agreement. Upon termination you will have
    90 days to exercise any vested options.

7.  To receive the benefits stated in this Transition Agreement, please confirm
    your receipt of this document by signing below, and by signing and returning
    the attached Release and Waiver within 45 days.

Do not hesitate to contact me with any questions.

Sincerely,



/s/ Crawford Beveridge
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Crawford Beveridge

Executive Vice President and Chief Human Resources Officer

I agree with the above terms:

/s/ Masood Jabbar                                  July 18, 2002
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Masood Jabbar                                      Date