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EXHIBIT 10.28



                           COMMERCIAL PROMISSORY NOTE
                                   (BASE RATE)

                                                           Annie Au / SR / 15787

Debtor Name
Sparta, Inc., a Delaware corporation

Debtor Address                            Office   Loan Number
23041 Avenida De La Carlota #325          45061    850-832-775-8  0080-00-0-000
Laguna Hills, CA 92653

                                          Maturity Date          Amount
                                          July 1, 2004        $6,000,000.00


Date June 14, 2002                                                 $6,000,000.00

FOR VALUE RECEIVED, on July 1, 2004,the undersigned ("Debtor") promises to
pay to the order of UNION BANK OF CALIFORNIA, N.A. ("Bank"), as indicated
below, the principal sum of Six Million and 00/100ths Dollars
($6,000,000.00), or so much thereof as is disbursed, together with interest
on the balance of such principal from time to time outstanding, at the per
annum rate or rates and at the times set forth below.

1. INTEREST PAYMENTS. Debtor shall pay interest on the 1st day of each month
commencing July 1, 2002. Should interest not be paid when due, it shall
become part of the principal and bear interest as herein provided. All
computations of interest under this note shall be made on the basis of a year
of 360 days, for actual days elapsed. If any interest rate defined in this
note ceases to be available from Bank for any reason, then said interest rate
shall be replaced by the rate then offered by Bank, which, in the sole
discretion of Bank, most closely approximates the unavailable rate.

     (a) BASE INTEREST RATE. At Debtor's option, amounts outstanding hereunder
     in minimum amounts of $100,000 shall bear interest at a rate, based on an
     index selected by Debtor, which is 2% per annum in excess of Bank's LIBOR
     Rate for the Interest Period selected by Debtor, acceptable to Bank.

     No Base Interest Rate may be changed, altered or otherwise modified until
     the expiration of the Interest Period selected by Debtor. The exercise of
     interest rate options by Debtor shall be as recorded in Bank's records,
     which records shall be prima facie evidence of the amount borrowed under
     either interest option and the interest rate; provided, however, that
     failure of Bank to make any such notation in its records shall not
     discharge Debtor from its obligations to repay in full with interest all
     amounts borrowed. In no event shall any Interest Period extend beyond the
     maturity date of this note.

     To exercise this option, Debtor may, from time to time with respect to
     principal outstanding on which a Base Interest Rate is not accruing, and on
     the expiration of any Interest Period with respect to principal outstanding
     on which a Base Interest Rate has been accruing, select an index offered by
     Bank for a Base Interest Rate Loan and an Interest Period by telephoning an
     authorized lending officer of Bank located at the banking office identified
     below prior to 10:00 a.m., Pacific time, on any Business Day and advising
     that officer of the selected index, the Interest Period and the Origination
     Date selected (which Origination Date, for a Base Interest Rate Loan based
     on the LIBOR Rate, shall follow the date of such selection by no more than
     two (2) Business Days).

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     Bank will mail a written confirmation of the terms of the selection to
     Debtor promptly after the selection is made. Failure to send such
     confirmation shall not affect Bank's rights to collect interest at the rate
     selected. If, on the date of the selection, the index selected is
     unavailable for any reason, the selection shall be void. Bank reserves the
     right to fund the principal from any source of funds notwithstanding any
     Base Interest Rate selected by Debtor.

     (b) VARIABLE INTEREST RATE. All principal outstanding hereunder which is
     not bearing interest at a Base Interest Rate shall bear interest at the
     Reference Rate, which rate shall vary as and when the Reference Rate
     changes.

At any time prior to the maturity date of this note, subject to the
provisions of paragraph 4 below, Debtor may borrow, repay and reborrow
hereunder so long as the total outstanding at any one time does not exceed
the principal amount of this note.

Debtor shall pay all amounts due under this note in lawful money of the
United States at Bank's Orange County Corporate Banking Office, or such other
office as may be designated by Bank, from time to time.

2. LATE PAYMENTS. If any payment required by the terms of this note shall remain
unpaid ten days after same is due, at the option of Bank, Debtor shall pay a fee
of $100 to Bank.

3. INTEREST RATE FOLLOWING DEFAULT. In the event of default, at the option of
Bank, and, to the extent permitted by law, interest shall be payable on the
outstanding principal under this note at a per annum rate equal to five
percent (5%) in excess of the interest rate specified in paragraph 1.b,
above, calculated from the date of default until all amounts payable under
this note are paid in full,

4. PREPAYMENT.

     (a) Amounts outstanding under this note bearing interest at a rate based on
     the Reference Rate may be prepaid in whole or in part at any time, without
     penalty or premium. Debtor may prepay amounts outstanding under this note
     bearing interest at a Base Interest Rate in whole or in part provided
     Debtor has given Bank not less than five (5) Business Days prior written
     notice of Debtors intention to make such prepayment and pays to Bank the
     prepayment fee due as a result. The prepayment fee shall also be paid, if
     Bank, for any other reason, including acceleration or foreclosure, receives
     all or any portion of principal bearing interest at a Base Interest Rate
     prior to its scheduled payment date. The prepayment fee shall be an amount
     equal to the present value of the product of: (i) the difference (but not
     less than zero) between (a) the Base Interest Rate applicable to the
     principal amount which is being prepaid, and (b) the return which Bank
     could obtain if it used the amount of such prepayment of principal to
     purchase at bid price regularly quoted securities issued by the United
     States having a maturity date most closely coinciding with the relevant
     Base Rate Maturity Date and such securities were held by Bank until the
     relevant Base Rate Maturity Date ("Yield Rate"); (ii) a fraction, the
     numerator of which is the number of days in the period between the date of
     prepayment and the relevant Base Rate Maturity Date and the denominator of
     which is 360; and (iii) the amount of the principal so prepaid (except in
     the event that principal payments are required and have been made as
     scheduled under the terms of the Base Interest Rate Loan being prepaid,
     then an amount equal to the lesser of (A) the amount prepaid or (B) 50% of
     the sum of (1) the amount prepaid and (2) the amount of principal scheduled
     under the terms of the Base Interest Rate Loan being prepaid to be
     outstanding at the relevant Base Rate Maturity Date). Present value under
     this note is determined by discounting the above product to present value
     using the Yield Rate as the annual discount factor.

     (b) In no event shall Bank be obligated to make any payment or refund to
     Debtor, nor shall Debtor be entitled to any setoff or other claim against
     Bank, should the return which Bank could

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     obtain under this prepayment formula exceed the interest that Bank would
     have received if no prepayment had occurred. All prepayments shall include
     payment of accrued interest on the principal amount so prepaid and shall be
     applied to payment of interest before application to principal. A
     determination by Bank as to the prepayment fee amount, if any, shall be
     conclusive.

     (c) Bank shall provide Debtor a statement of the amount payable on account
     of prepayment. Debtor acknowledges that (i) Bank establishes a Base
     Interest Rate upon the understanding that it apply to the Base Interest
     Rate Loan for the entire Interest Period, and (ii) Bank would not lend to
     Debtor without Debtor's express agreement to pay Bank the prepayment fee
     described above.

  DEBTOR INITIAL HERE:     /s/ RCS     /s/ DES


5. DEFAULT AND ACCELERATION OF TIME FOR PAYMENT. Default shall include, but not
be limited to, any of the following: (a) the failure of Debtor to make any
payment required under this note when due; (b) any breach, misrepresentation or
other default by Debtor, any guarantor, co-maker, endorser, or any person or
entity other than Debtor providing security for this note (hereinafter
individually and collectively referred to as the "Obligor") under any security
agreement, guaranty or other agreement between Bank and any Obligor; (c) the
insolvency of any Obligor or the failure of any Obligor generally to pay such
Obligor's debts as such debts become due; (d) the commencement as to any Obligor
of any voluntary or involuntary proceeding under any laws relating to
bankruptcy, insolvency, reorganization, arrangement, debt adjustment or debtor
relief; (e) the assignment by any Obligor for the benefit of such Obligor's
creditors; (f) the appointment, or commencement of any proceeding for the
appointment of a receiver, trustee, custodian or similar official for all or
substantially all of any Obligor's property; (g) the commencement of any
proceeding for the dissolution or liquidation of any Obligor; (h) the
termination of existence or death of any Obligor; (i) the revocation of any
guaranty or subordination agreement given in connection with this note; (j) the
failure of any Obligor to comply with any order, judgement, injunction, decree,
writ or demand of any court or other public authority; (k) the filing or
recording against any Obligor, or the property of any Obligor, of any notice of
levy, notice to withhold, or other legal process for taxes other than property
taxes; (l) the default by any Obligor personally liable for amounts owed
hereunder on any obligation concerning the borrowing of money; (m) the issuance
against any Obligor, or the property of any Obligor, of any writ of attachment,
execution, or other judicial lien; or (n) the deterioration of the financial
condition of any Obligor which results in Bank deeming itself, in good faith,
insecure. Upon the occurrence of any such default, Bank, in its discretion, may
cease to advance funds hereunder and may declare all obligations under this note
immediately due and payable; however, upon the occurrence of an event of default
under d, e, f, or g, all principal and interest shall automatically become
immediately due and payable.

6. ADDITIONAL AGREEMENTS OF DEBTOR. If any amounts owing under this note are not
paid when due, Debtor promises to pay all costs and expenses, including
reasonable attorneys' fees, (including the allocated costs of Bank's in-house
counsel and legal staff) incurred by Bank in the negotiation, documentation and
modification of this note and all related documents and in the collection or
enforcement of any amount outstanding hereunder. Debtor and any Obligor, for the
maximum period of time and the full extent permitted by law, (a) waive
diligence, presentment, demand, notice of nonpayment, protest, notice of
protest, and notice of every kind; (b) waive the right to assert the defense of
any statute of limitations to any debt or obligation hereunder; and (c) consent
to renewals and extensions of time for the payment of any amounts due under this
note. If this note is signed by more than one party, the term "Debtor' includes
each of the undersigned and any successors in interest thereof; all of whose
liability shall be joint and several. Any married person who signs this note
agrees that recourse may be had against the separate property of that person for
any obligations hereunder. The receipt of any check or ether item of payment by
Bank, at its option, shall not be considered a payment on account until such
check or other item of payment is honored when presented for payment at the
drawee bank. Bank may delay the credit of such payment based upon Bank's
schedule of funds availability, and interest under this note shall accrue until
the funds are deemed collected. In any action brought under or

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arising out of this note, Debtor and any Obligor, including their successors and
assigns, hereby consent to the jurisdiction of any competent court within the
State of California, as provided in any alternative dispute resolution agreement
executed between Debtor and Bank, and consent to service of process by any means
authorized by said state's law. The term "Bank" includes, without limitation,
any holder of this note. This note shall be construed in accordance with and
governed by the laws of the State of California. This note hereby incorporates
any alternative dispute resolution agreement previously, concurrently or
hereafter executed between Debtor and Bank.

7. DEFINITIONS. As used herein, the following terms shall have the meanings
respectively set forth below: "Base Interest Rate" means a rate of interest
based on the LIBOR Rate. "Base Interest Rate Loan" means amounts outstanding
under this note that bear interest at a Base Interest Rate. "Base Rate Maturity
Date" means the last day of the Interest Period with respect to principal
outstanding under a Base Interest Rate Loan. "Business Day" means a day on which
Bank is open for business for the funding of corporate loans, and, with respect
to the rate of interest based on the LIBOR Rate, on which dealings in U.S.
dollar deposits outside of the United States may be carried on by Bank.
"Interest Period" means with respect to funds bearing interest at a rate based
on the LIBOR Rate, any calendar period of 1, 3, 6, 9 or 12 months. In
determining an Interest Period, a month means a period that starts on one
Business Day in a month and ends on and includes the day preceding the
numerically corresponding day in the next month. For any month in which there is
no such numerically corresponding day, then as to that month, such day shall be
deemed to be the last calendar day of such month. Any Interest Period which
would otherwise end on a non-Business Day shall end on the next succeeding
Business Day unless that is the first day of a month, in which event such
Interest Period shall end on the next preceding Business Day. "LIBOR Rate" means
a per annum rate of interest (rounded upward, if necessary, to the nearest 1/100
of 1%) at which dollar deposits, in immediately available funds and in lawful
money of the United States would be offered to Bank, outside of the United
States, for a term coinciding with the Interest Period selected by Debtor and
for an amount equal to the amount of principal covered by Debtors interest rate
selection, plus Bank's costs, including the cost, if any, of reserve
requirements. "Origination Date" means the first day of the Interest Period.
"Reference Rate" means the rate announced by Bank from time to time at its
corporate headquarters as its Reference Rate. The Reference Rate is an index
rate determined by Bank from time to time as a means of pricing certain
extensions of credit and is neither directly tied to any external rate of
interest or index nor necessarily the lowest rate of interest charged by Bank at
any given time.


DEBTOR:
Sparta, Inc.,  a Delaware corporation

By:  /s/ Robert C. Sepucha
     --------------------------------
     Robert C. Sepucha
     President/CEO

By:  /s/ David E. Schreiman
     --------------------------------
     David E. Schreiman
     Vice President and Chief Financial Officer