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                                                                    Exhibit 10.5


     1.   If, at any time during the first twelve months of your employment by
the Company, the Company terminates your employment following a Change in
Control or for reasons other than Cause, or if you terminate your employment
following a Change in Control for Good Reason, you will be entitled to receive
from the Company the following severance benefits, in lieu of all other salary
and benefits:

          a.   CONTINUED COMPENSATION. The Company will pay you your base salary
     at the rate in effect at the time of the termination of your employment,
     for a period of six months following the termination date, or until you
     obtain other full-time employment, whichever is sooner.

          b.   HEALTH CARE AND LIFE INSURANCE COVERAGE. The Company will provide
     continued health care coverage under the Company's medical plan, without
     charge, to you and your eligible dependents until the earlier of (i) six
     months following the termination date or (ii) the first date that you are
     covered under another employer's health benefit program providing
     substantially the same or better benefit options without exclusion for any
     pre-existing medical condition. The period of time medical coverage
     continues under this agreement will be counted as coverage time under
     COBRA.

     A "Change in Control" shall occur if any person or related group of persons
(other than the Company or a person that, prior to such transaction, directly or
indirectly controls, is controlled by, or is under common control with, the
Company) directly acquires beneficial ownership of securities possessing more
than fifty percent (50%) of the total combined voting power of the Company's
outstanding securities.

     "Cause" means any of the following events: (i) any act of gross or willful
misconduct, fraud, misappropriation, dishonesty, embezzlement or similar conduct
on your part; (ii) your conviction of a felony or any crime involving moral
turpitude (which conviction, due to the passage of time or otherwise, is not
subject to further appeal); (iii) your misuse or abuse of alcohol, drugs or
controlled substances and failure to seek and comply with appropriate treatment;
or (iii) your becoming disabled such that you are not able to performing your
usual duties for the Company for a period in excess of six (6) consecutive
calendar months.

     "Good Reason" means any of the following events, if you have not consented
thereto: (i) a substantial diminution in your duties and responsibilities
hereunder; (ii) the Company headquarters are moved more than 30 miles from its
present location in San Diego, California; (iii) a material reduction in your
base salary or benefits from the Company, other than in connection with an
across-the-board reduction for all similarly situated employees; provided,
however, that no change in ownership or control of the Company shall itself
constitute Good Reason; and provided, further, that an insubstantial and
inadvertent action which is remedied by the Company promptly after receipt of
notice thereof given by you shall not constitute Good Reason hereunder. Your
consent to any event which would otherwise constitute Good Reason shall be
conclusively

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presumed if you do not exercise your rights to terminate your employment for
Good Reason under this section within sixty (60) days of the event.

     2.   Any and all compensation to be paid under this agreement will be
subject to the Company's collection of all applicable federal, state and local
income and employment withholding taxes.

     3.   Nothing in this agreement shall be construed as giving you any rights
to continued employment with the Company, and the Company shall continue to
have the right to terminate your employment at any time, with or without cause,
subject to the provisions of this Agreement.


     /s/ Herm Rosenman            /s/ Robin L. Vedova
     -----------------            -------------------
     Herm Rosenman                Robin L. Vedova

     5/24/01                       5/24/01
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     Date                          Date




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