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                                                                   EXHIBIT 10.15


                                 PROMISSORY NOTE


$1,041,481.77                                           Los Angeles, California
                                                        December 31, 2002

         FOR VALUE RECEIVED, the undersigned, US DATAWORKS, INC., a Nevada
corporation ("Maker"), hereby unconditionally promises to pay to the order of
ACI COMMUNICATIONS HOLDINGS, INC. f/k/a ALLSTATE COMMUNICATIONS, INC., a
California corporation ("Payee"), at Payee's offices located at 21621 Nordhoff
Street, Chatsworth, California 91311, or such place as may be designated by the
holder of this Promissory Note from time to time, the principal sum of ONE
MILLION, FORTY-ONE THOUSAND FOUR HUNDRED EIGHTY-ONE AND 77/100 DOLLARS
($1,041,481.77) with interest on the unpaid principal balance from the date
hereof until repaid at a rate per annum equal to TEN PERCENT (10%), computed on
the basis of a 365-day year and actual time elapsed, both principal and interest
to be paid in lawful money of the United States of America in the following
schedule:

                  (i) THIRTY-FIVE THOUSAND AND NO/100 DOLLARS ($35,000.00) per
month for the months of January through December of 2003. All payments shall be
due on or before the twentieth (20th) day of each month (the "Monthly Due
Date"); and

                  (ii) additional payments that constitute FIFTEEN PERCENT (15%)
of all proceeds from any Financings, payable within three (3) business days of
Maker's receipt of funds (such date, the "Financing Date"), until the Promissory
Note is paid in full. For purposes of this Promissory Note, the term
"Financings" shall mean Maker's receipt of not less than ONE HUNDRED THOUSAND
DOLLARS ($100,000) of new capital invested into Maker from any Third Party
Investor; EXCLUDING, any debt or capital restructuring of Maker or the exercise
of any warrant outstanding as of even date herewith. For purposes of this
Promissory Note, the term "Third Party Investor" does not include Charles Ramey
or any commercial lending entity providing funding to Maker for the specific
purpose of facilitating the installation of Maker's products with a licensee.


         All amounts received from Maker shall first be applied to accrued and
unpaid interest, except in the case of default, at which time amounts received
may first be applied against costs and expenses of collection. Notwithstanding
any payments by Maker, any unpaid balance and all accrued and unpaid interest of
this Promissory Note shall be paid to Payee no later than December 31, 2003 (the
"Maturity Date"). Maker may prepay this Promissory Note at any time prior to the
Maturity Date without penalty. Payee shall extend to Maker a five (5) business
day grace period ("Grace Period") beyond the Financing Date, Monthly Due Date
and Maturity Date on payment of the Promissory Note; after the five (5) business
day grace period, any past due amount shall accrue additional interest at the
rate of TEN PERCENT (10%) per annum (any past due amount and interest accrued
thereon hereinafter referred to as the "Past Due Amount"), commencing from the
corresponding the Financing Date, Monthly Due Date and Maturity Date. Maker will


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be entitled to use the Grace Period for not more than two (2) occasions during
the term of this Promissory Note. If (a) any portion of the Past Due Amount
remains due and outstanding for a period greater than thirty (30) days following
the corresponding Financing Date, Monthly Due Date or Maturity Date (unless a
longer cure period is mutually agreed by the parties), or (b) Maker fails to
make the corresponding payment on or before the Financing Date, Monthly Due Date
or Maturity Date for a third time during the term of the Promissory Note, then
Payee at its option may declare the principal of this Promissory Note, and any
other amounts owing hereunder, to be immediately due and payable whereupon such
amounts shall forthwith become due and payable without notice, presentment,
demand, protest, notice of intention to accelerate, notice of acceleration or
other notice of any kind, all of which Maker hereby expressly waives.

         Should Maker fail to pay the Payee the Past Due Amount within thirty
(30) days following Maker's receipt of Payee's "Notice of Breach" (as such term
is defined in that certain Security Agreement entered into by and between Maker
and Payee on even date herewith; the "Security Agreement"), then such failure to
pay shall constitute an "Event of Default" as described in the Security
Agreement.

         Notwithstanding anything in this Promissory Note to the contrary,
Maker, and any and all endorsers, sureties hereof and all other persons liable
or to become liable hereon, severally waive presentment for payment, demand,
notice of demand and of dishonor and nonpayment of this Promissory Note, protest
and notice of protest, diligence in collecting and bringing suit against any
other party, and agree to all renewals, extension, modifications, partial
payments, releases or substitutions of security, in whole or in part, with or
without notice, before or after the Maturity Date. The pleading of the statute
of limitations as a defense to any demand against the makers, endorsers,
guarantors and sureties hereof is expressly waived by each and all such parties
to the extent permitted by law.

         Notwithstanding anything herein to the contrary, at no time shall any
amounts payable on or under this Promissory Note, to the extent such amounts are
construed to constitute a late fee, finance charge or interest, exceed the
maximum rate or amount thereof permitted by law. If, at any time, the applicable
rate or amount computed in the manner provided in this Promissory Note exceeds
the maximum lawful rate or amount which may be charged (the "Maximum Rate"),
such rate or amount shall be limited to the Maximum Rate. If and for so long as
any applicable law is ever judicially interpreted so as to render usurious any
amount called for under this Promissory Note, all excess amounts collected by
Payee shall be credited to the outstanding principal balance hereof and the
amounts thereafter collectible hereunder reduced, without the necessity of the
execution of any new document, so as to comply with such applicable law and
permit the recovery of the fullest amount otherwise called for hereunder.

         This Promissory Note shall be construed and enforced in accordance with
the laws of the State of California.

US DATAWORKS, INC.
A Nevada Corporation

By:      /S/ CHARLES RAMEY
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Name:    CHARLES RAMEY
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Its:     CEO
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