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                                                                   EXHIBIT 10.16



                             SECURED PROMISSORY NOTE
                            (REVOLVING CREDIT LOANS)

$10,000,000                                             LOS ANGELES, CALIFORNIA
                                                        OCTOBER 29, 1999

        FOR VALUE RECEIVED, the undersigned (Borrower) promises to pay to the
order of GREYROCK CAPITAL, a division of Banc of America Commercial Finance
Corporation (Greyrock), at 10880 Wilshire Blvd. Suite 950, Los Angeles, CA
90024, or at such other address as the holder of this Note shall direct, the
principal sum of $10,000,000, or so much of said sum as Greyrock shall have
advanced to Borrower pursuant to the Loan Agreement described below, payable on
the earlier of the following dates (the Maturity Date): (i) February 1, 2001, or
(ii) the date the Loan and Security Agreement between Borrower and Greyrock
dated OCTOBER 29, 1999 (the Loan Agreement) terminates by its terms or is
terminated by either party in accordance with its terms. On the Maturity Date
the entire remaining unpaid principal balance of this Note, plus any and all
accrued and unpaid interest, shall be due and payable.

        This Note shall bear interest on the unpaid principal balance hereof
from time to time outstanding at a rate equal to the following: The interest
rate in effect throughout each calendar month during the term of this Note shall
be the highest Prime Rate in effect during such month, plus 2% per annum,
provided that the interest rate in effect in each month shall not be less than
8% per annum. Interest shall be calculated on the basis of a 360-day year for
the actual number of days elapsed. Prime Rate has the meaning set forth in the
Loan Agreement.

        Accrued interest on this Note shall be payable monthly, commencing on
October 31, 1999, and continuing on the last day of each succeeding month. Any
accrued interest not paid when due shall bear interest at the same rate as the
principal hereunder.

        Principal of and interest on this Note shall be payable in lawful money
of the United States of America. If a payment hereunder becomes due and payable
on a Saturday, Sunday or legal holiday, the due date thereof shall be extended
to the next succeeding business day, and interest shall be payable thereon
during such extension.

        In the event any payment of principal or interest on this Note is not
paid in full when due, or if any other default or event of default occurs
hereunder, under the Loan Agreement or under any other present or future
instrument, document, or agreement between Borrower and Greyrock (collectively,
Events of Default), Greyrock may, at its option, at any time thereafter, declare
the entire unpaid principal balance of this Note plus all accrued interest to be
immediately due and payable, without notice or demand. The acceptance of any
installment of principal or interest by Greyrock after the time when it becomes
due, as herein specified, shall not be held to establish a custom, or to waive
any rights of Greyrock to enforce payment when due of any further installments
or any other rights, nor shall any failure or delay to exercise any rights be
held to waive the same.

        All payments hereunder are to be applied first to costs and fees
referred to hereunder, second to the payment of accrued interest and the
remaining balance to the payment of principal. Any principal prepayment
hereunder shall be applied against principal payments in the inverse order of
maturity. Greyrock shall have the continuing and exclusive right to apply or
reverse and reapply any and all payments hereunder.

        The Borrower agrees to pay all costs and expenses (including without
limitation attorney's fees) incurred by Greyrock in connection with or related
to this Note, or its enforcement, whether or not suit be brought. The Borrower
hereby waives presentment, demand for payment, notice of dishonor, notice of
nonpayment, protest, notice of protest, and any and all other notices and
demands in connection with the delivery, acceptance, performance, default, or
enforcement of this Note, and Borrower hereby waives



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the benefits of any statute of limitations with respect to any action to
enforce, or otherwise related to, this Note.

        This Note is secured by the Loan Agreement and all other present and
future security agreements between Borrower and Greyrock. Nothing herein shall
be deemed to limit any of the terms or provisions of the Loan Agreement or any
other present or future document, instrument or agreement, between Borrower and
Greyrock, and all of Greyrock's rights and remedies hereunder and thereunder are
cumulative.

        In the event any one or more of the provisions of this Note shall for
any reason be held to be invalid, illegal or unenforceable, the same shall not
affect any other provision of this Note and the remaining provisions of this
Note shall remain in full force and effect.

        No waiver or modification of any of the terms or provisions of this Note
shall be valid or binding unless set forth in a writing signed by a duly
authorized officer of Greyrock, and then only to the extent therein specifically
set forth. If more than one person executes this Note, their obligations
hereunder shall be joint and several.

GREYROCK AND BORROWER EACH HEREBY WAIVE THE RIGHT TO TRIAL BY JURY IN ANY ACTION
OR PROCEEDING BASED UPON, ARISING OUT OF, OR IN ANY WAY RELATING TO: (i) THIS
NOTE; OR (ii) ANY OTHER PRESENT OR FUTURE INSTRUMENT OR AGREEMENT BETWEEN
GREYROCK AND BORROWER; OR (iii) ANY CONDUCT, ACTS OR OMISSIONS OF GREYROCK OR
BORROWER OR ANY OF THEIR DIRECTORS, OFFICERS, EMPLOYEES, AGENTS, ATTORNEYS OR
ANY OTHER PERSONS AFFILIATED WITH GREYROCK OR BORROWER; IN EACH OF THE FOREGOING
CASES, WHETHER SOUNDING IN CONTRACT OR TORT OR OTHERWISE.

        This Note is payable in, and shall be governed by the laws of, the State
of California.


                                             SOFTWARE TECHNOLOGIES CORPORATION


                                             By /s/ WILLIAM OVERELL
                                               ---------------------------------
                                             Title CHIEF FINANCIAL OFFICER
                                                   -----------------------------



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                             SECURED PROMISSORY NOTE
                                   (TERM LOAN)

$10,000,000                                             LOS ANGELES, CALIFORNIA
                                                        OCTOBER 29, 1999

        FOR VALUE RECEIVED, the undersigned (Borrower) promises to pay to the
order of GREYROCK CAPITAL, a division of Banc of America Commercial Finance
Corporation (Greyrock), at 10880 Wilshire Blvd. Suite 950, Los Angeles, CA
90024, or at such other address as the holder of this Note shall direct, the
principal sum of $10,000,000, payable on the earlier of the following dates (the
Maturity Date): (i) February 1, 2001, or (ii) the date the Loan and Security
Agreement between Borrower and Greyrock dated OCTOBER 29, 1999 (the Loan
Agreement) terminates by its terms or is terminated by either party in
accordance with its terms. On the Maturity Date the entire remaining unpaid
principal balance of this Note, plus any and all accrued and unpaid interest,
shall be due and payable.

        This Note shall bear interest on the unpaid principal balance hereof
from time to time outstanding at a rate equal to the following: The interest
rate in effect throughout each calendar month during the term of this Note shall
be the highest Prime Rate in effect during such month, plus 2% per annum,
provided that the interest rate in effect in each month shall not be less than
8% per annum. Interest shall be calculated on the basis of a 360-day year for
the actual number of days elapsed. Prime ate has the meaning set forth in the
Loan Agreement.

        Accrued interest on this Note shall be payable monthly, commencing on
October 31, 1999, and continuing on the last day of each succeeding month. Any
accrued interest not paid when due shall bear interest at the same rate as the
principal hereunder.

        Principal of and interest on this Note shall be payable in lawful money
of the United States of America. If a payment hereunder becomes due and payable
on a Saturday, Sunday or legal holiday, the due date thereof shall be extended
to the next succeeding business day, and interest shall be payable thereon
during such extension.

        In the event any payment of principal or interest on this Note is not
paid in full when due, or if any other default or event of default occurs
hereunder, under the Loan Agreement or under any other present or future
instrument, document, or agreement between Borrower and Greyrock (collectively,
Events of Default), Greyrock may, at its option, at any time thereafter, declare
the entire unpaid principal balance of this Note plus all accrued interest to be
immediately due and payable, without notice or demand. The acceptance of any
installment of principal or interest by Greyrock after the time when it becomes
due, as herein specified, shall not be held to establish a custom, or to waive
any rights of Greyrock to enforce payment when due of any further installments
or any other rights, nor shall any failure or delay to exercise any rights be
held to waive the same.

        All payments hereunder are to be applied first to costs and fees
referred to hereunder, second to the payment of accrued interest and the
remaining balance to the payment of principal. Any principal prepayment
hereunder shall be applied against principal payments in the inverse order of
maturity. Greyrock shall have the continuing and exclusive right to apply or
reverse and reapply any and all payments hereunder.

        The Borrower agrees to pay all costs and expenses (including without
limitation attorney's fees) incurred by Greyrock in connection with or related
to this Note, or its enforcement, whether or not suit be brought. The Borrower
hereby waives presentment, demand for payment, notice of dishonor, notice of
nonpayment, protest, notice of protest, and any and all other notices and
demands in connection with the delivery, acceptance, performance, default, or
enforcement of this Note, and Borrower hereby waives



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<PAGE>   4

the benefits of any statute of limitations with respect to any action to
enforce, or otherwise related to, this Note.

        This Note is secured by the Loan Agreement and all other present and
future security agreements between Borrower and Greyrock. Nothing herein shall
be deemed to limit any of the terms or provisions of the Loan Agreement or any
other present or future document, instrument or agreement, between Borrower and
Greyrock, and all of Greyrock's rights and remedies hereunder and thereunder are
cumulative.

        In the event any one or more of the provisions of this Note shall for
any reason be held to be invalid, illegal or unenforceable, the same shall not
affect any other provision of this Note and the remaining provisions of this
Note shall remain in full force and effect.

        No waiver or modification of any of the terms or provisions of this Note
shall be valid or binding unless set forth in a writing signed by a duly
authorized officer of Greyrock, and then only to the extent therein specifically
set forth. If more than one person executes this Note, their obligations
hereunder shall be joint and several.

GREYROCK AND BORROWER EACH HEREBY WAIVE THE RIGHT TO TRIAL BY JURY IN ANY ACTION
OR PROCEEDING BASED UPON, ARISING OUT OF, OR IN ANY WAY RELATING TO: (i) THIS
NOTE; OR (ii) ANY OTHER PRESENT OR FUTURE INSTRUMENT OR AGREEMENT BETWEEN
GREYROCK AND BORROWER; OR (iii) ANY CONDUCT, ACTS OR OMISSIONS OF GREYROCK OR
BORROWER OR ANY OF THEIR DIRECTORS, OFFICERS, EMPLOYEES, AGENTS, ATTORNEYS OR
ANY OTHER PERSONS AFFILIATED WITH GREYROCK OR BORROWER; IN EACH OF THE FOREGOING
CASES, WHETHER SOUNDING IN CONTRACT OR TORT OR OTHERWISE.

        This Note is payable in, and shall be governed by the laws of, the State
of California.


                                             SOFTWARE TECHNOLOGIES CORPORATION


                                             By /s/ WILLIAM OVERELL
                                               ---------------------------------
                                             Title CHIEF FINANCIAL OFFICER
                                                   -----------------------------



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