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                                                                   EXHIBIT 10.10



January 28, 2000



Mr. Bud Mullanix



Dear Bud:

OSI is pleased to confirm our offer of employment to you for the position Vice
President, Human Resources, in our Folsom location.  In this position you will
be reporting to me for a period not to exceed 90 days, after which you will
report to our Co-Chief Executive Officers.  Your anticipated start date will be
February 14, 2000.

   Base Salary:     $130,000 per year.
   Incentive Plan:  OSI's standard Executive Compensation Plan, which currently
                    is structured to pay out 50% of base at target performance.

Option Grant.  At the first meeting of the Board of Directors after your hire
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date, and subject to approval of the Board, you will be granted an option to
purchase 50,000 shares of OSI's common stock.  The option price will be the Fair
market Value of OSI stock on the date the Board approves your grant.  Options
will vest over 4 years from the grant date, as follows:  as long as you continue
to meet the vesting requirements in our Option Plan, your right to acquire 25%
of the shares under option will vest 12 months after the grant date, and your
right to acquire 1/48 of the shares under option will vest each month
thereafter.  Vesting will be tolled when you are on a leave of absence except as
otherwise required by law.  This is a general summary.  The actual terms of
option grants are as set forth in the Option Plan and Grant Agreement, both of
which that will be given to you at the time your grant is approved.

Standard Benefits.  Insurance benefits will be effective on the first day of the
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month following completion of 30 calendar days of employment.  During your first
year, you will earn three weeks of vacation/sick time in accordance with our
standard policies.  You may contribute any amount of your before tax
compensation, subject to the limits imposed by the Internal Revenue Service, to
the OSI 410(k) Plan.  You may also participate in the OSI Employee Stock
Purchase Plan beginning with the first Plan enrollment date after you begin
work.  Enrollment dates for the ESPP are April 30 and October 31.  Finally,
based on our success and profitability, you may receive the benefit of
discretionary contributions to the OSI Profit Sharing Plan.  Provided you
satisfy  the eligibility requirements of that Plan (currently, completion of 90
days of employment and over 1000 hours of service in a Plan year, which runs
from July 1 through June 30), contributions are made at the end of each fiscal
year.

Notwithstanding the above, during the period from the commencement of your
employment with OSI through your eligibility for coverage under OSI's standard
insurance benefits, we will reimburse you for any amounts that are actually paid
by you to obtain extended COBRA coverage for your insurance benefits at your
current employer.

Severance Agreement.  Promptly following your employment, OSI will enter into
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its standard Severance Agreement with you.  This Agreement provides for certain
salary continuation and other benefit in the event OSI has a Change in Control,
as more particularly defined.  A copy of that Agreement is attached.
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Bud Mullanix
January 28, 2000
Page 2


Representations.  As a condition to our offer of employment, you represent and
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acknowledge that (1) your resume and employment application are complete and
accurate and do not contain any material misstatements, and (2) you have not
been convicted of any crime or found liable criminally or civilly for any action
or omission involving fraud, dishonesty or moral turpitude.

Contingencies.  We reserve the right to investigate your prior employment
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history, personal references and educational background, as well as other
relevant information that is reasonably available to us.  We may also review
your credit report, driving record and criminal background.  Consistent with
legal requirements, your offer of employment is contingent on a satisfactory
background check.  Under the Immigration and Naturalization Act of 1986, your
offer is also contingent on your ability to provide proof of your right to work
and your completion of an INS Form I-9.

Legal Matters.  Please not that, as a condition of employment, you mist enter
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into an agreement to arbitrate all disputes arising out of or related to your
employment.  This includes any issues related to the termination of your
employment and any claims of unlawful discrimination or unlawful harassment,
including sexual harassment.  Only an arbitrator, and not a judge or a jury,
will hear these disputes.  In addition, you must sign the attached Employee
Invention Agreement.

General.  Your employment at OSI will be governed by the traditional legal
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principals of employment at will.  Both you and OSI have the right to terminate
the employment relationship at any time, with or without notice and with or
without cause.  Except for the policies of at-will employment and mandatory
arbitration, we reserve the right to modify the terms and conditions of your
employment, including your compensation and your benefits.  You agree at all
times to comply with OSI's policies communicated to you and with all applicable
laws, regulations, codes and ordinances.

OSI is eager for you to join us and encourage you to accept this rewarding and
challenging opportunity.  We would appreciate your signing this letter below and
returning it to the undersigned as soon as possible, along with your signed
Employee Invention Agreement, your signed acknowledgement of our Alternative
Dispute Resolution Policy and your completed I-9.  Please return copies of
supporting identification(s) specified on the Form I-9 or be prepared to provide
them on your first day of employment.

This letter contains all of the details relating to our offer of employment.  No
one has the authority to modify or add new terms or conditions without the
signed approval of an OSI officer.  Please feel free to contact me at (916) 353-
2400, extension 2773, if you have any questions or concerns.  This offer will be
rescinded within seven working days if no reply is received.

Sincerely,                           Accepted by:



/s/ Philip N. Cardman                /s/ Bud Mullanix
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Philip N. Cardman                            Bud Mullanix               Date
Vice President