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                                 April 25, 2000

Mr. Darwin Deason
c/o Affiliated Computer Services, Inc.
2828 North Haskell Avenue
10th Floor
Dallas, Texas 75201

Re:      CREDIT AGREEMENT (THE "CREDIT AGREEMENT") DATED MARCH 22, 1999, BY AND
         AMONG PRECEPT BUSINESS SERVICES, INC. ("PRECEPT"), BANK ONE, TEXAS,
         N.A. AS CONTRACTUAL REPRESENTATIVE ("AGENT") FOR ITSELF AND THE OTHER
         LENDERS (COLLECTIVELY, THE "LENDERS"), AS HERETOFORE AMENDED AND AS
         AMENDED BY THAT CERTAIN AMENDMENT AND WAIVER NO. 3 (THE "AMENDMENT")
         DATED AS OF APRIL 27, 2000, AMONG PRECEPT, AGENT AND THE LENDERS
         (CAPITALIZED TERMS USED BUT NOT OTHERWISE DEFINED SHALL HAVE THE
         MEANING GIVEN TO SUCH TERMS IN THE CREDIT AGREEMENT AND THE AMENDMENT)

Dear Mr. Deason:

         As a condition to the Amendment and the extension of additional credit
to Precept, Lenders have requested that you guarantee payment when due of all
"Secured Obligations" (as defined in the Credit Agreement) up to the principal
amount of $2,266,000, plus interest and expenses of enforcement, pursuant to
that certain Limited Guaranty dated as of April 27, 2000 to be executed by you
and accepted by Agent on behalf of the Lenders (the "Additional Guaranty"). In
consideration of your executing and delivering the Additional Guaranty, Precept
agrees as follows:

         (1)      In the event demand is made upon you to pay any amounts under
the Additional Guaranty (the "Payment Obligation"), Precept shall pay such
amount to Bank One for the benefit of the Lenders. If Precept does not pay such
amount directly and you are required to make any payment under the Additional
Guaranty, Precept agrees to reimburse you on demand for the amount of such
payment, together with interest from the date of payment at the Default Rate
(which amount Precept hereby promises to pay). In the event demand is made upon
you to provide collateral security for the Additional Indebtedness as provided
in Section 2(b) of the Additional Guaranty (the "Collateral Obligation"),
Precept shall provide such collateral security (or other collateral security
acceptable to Lenders) to Agent for the benefit of the Lenders. If Precept does
not provide such collateral security and you are required to provide it as
therein


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required, Precept agrees to reimburse you on demand for the value of such
collateral security, together with interest from the date that such security is
provided at the Default Rate (which amount Precept hereby promises to pay). IN
ADDITION TO THE AFOREMENTIONED REIMBURSEMENT OBLIGATIONS, PRECEPT AGREES TO PAY
AND INDEMNIFY YOU AND HOLD YOU FREE AND HARMLESS FROM AND AGAINST (A) ANY LOSS,
COST, LIABILITY OR EXPENSE (INCLUDING ATTORNEYS' FEES AND EXPENSES) INCURRED IN
CONNECTION WITH ANY OF THE FOREGOING, INCLUDING, WITHOUT LIMITATION, THE DEFENSE
OF THE ADDITIONAL GUARANTY, PERFORMANCE OF THE PAYMENT OBLIGATION, PERFORMANCE
OF THE COLLATERAL OBLIGATION, ENFORCEMENT OF THE AGREEMENTS HEREIN CONTAINED, OR
OTHERWISE, AND (B) ALL EXPENSES (INCLUDING ATTORNEYS' FEES AND EXPENSES)
INCURRED IN CONNECTION WITH THE MAKING OR PERFORMANCE OF THE ADDITIONAL GUARANTY
OR THIS AGREEMENT.

         (2)      Furthermore, if the Guaranteed Amount (as determined pursuant
to Section 3 of the Additional Guaranty) (the "Guaranteed Amount") is not paid
in full in cash and the Letters of Credit issued under the Credit Agreement are
not terminated or expired, or a Release Event (as defined in the Additional
Guaranty) has not occurred, by October 22, 2000, Precept agrees to pay or
deliver to you at your option either (A) a number of shares of Precept's Series
A Convertible Preferred Stock, par value $1.00 per share ("Preferred Shares"),
and Common Stock Purchase Warrants in the form attached as Exhibit A (the
"Warrants") to the Securities Purchase Agreement dated as of or about April 19,
2000 between Precept and the Shaar Fund Ltd. ("Shaar" and the "Shaar Agreement")
equal to the number of Preferred Shares and Warrants that would have been issued
if the Guaranteed Amount then outstanding had been applied to the purchase of
Preferred Shares and Warrants for the same price and otherwise on the same terms
and conditions specified in the Shaar Agreement, such Preferred Shares and
Warrants to be entitled to the benefit of all representations, warranties,
covenants, rights and other benefits provided to Shaar under the Shaar Agreement
and all related undertakings and agreements or (B) such mutually acceptable
consideration to you having a value equivalent to the instruments you would have
received pursuant to (A) above; PROVIDED you shall exercise your rights
hereunder in a manner that does not contravene NASD Rule 4310(c)(25)(G).

         (3)      The term of this Agreement shall commence as of the date
hereof and continue in effect until all Guaranteed Obligations (as defined in
the Additional Guaranty) are terminated or extinguished (but not by reason of
the payment of the obligations by you).

         (4)      Precept represents and warrants to you that the making and
performance of this Agreement (a) have been duly approved by the Board of
Directors of Precept and any other necessary corporate action on the part of
Precept and (b) do not, and will not, subject to the terms of the Credit
Agreement, conflict with any agreement, order or obligation to which Precept is
a party or is otherwise bound. You acknowledge that your enforcement of the
terms of paragraph 1 above are subject to the terms of the Additional Guaranty.
Until the Secured Obligations have been indefeasibly paid in full in cash, you
have no right to enforce any of the reimbursement or


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indemnification obligations of Precept set forth in paragraph 1 above. Should
you have the right, notwithstanding the foregoing, to exercise any such rights
in paragraph 1 or to receive consideration other than securities pursuant to
paragraph 2, you hereby expressly and irrevocably (a) subordinate any and all
such rights at law or in equity that you may have to the indefeasible payment in
full in cash of the Secured Obligations, and (b) agree to turn over to the Agent
for application to the Secured Obligations any and all amounts, or payments
(other than the securities received pursuant to paragraph 2 above or
reimbursement of attorneys fees pursuant to paragraph 1(B) above) received by
you in connection with this Agreement until the Secured Obligations are
indefeasibly paid in full in cash. You acknowledge and agree that the provisions
of this paragraph are intended to benefit the Agent and the "Holders of Secured
Obligations" (as defined in the Credit Agreement) and that the Agent, the
Holders of Secured Obligations and their respective successors and assigns are
intended third party beneficiaries of the provisions set forth in this
paragraph.

         (5)      This Agreement constitutes the entire agreement of the parties
hereto with respect to the subject matter hereof and supersedes all prior
agreements and understandings, both written and verbal, between the parties
hereto with respect to the subject matter hereof.

         (6)      This Agreement shall be construed in accordance with and
governed by the laws of the State of Texas, without regard to choice of law
principles of such laws.

         (7)      The parties hereto may execute this Agreement in multiple
counterparts, all of which taken together shall constitute one and the same
instrument and each of which shall be deemed to be an original instrument as
against any party who as signed it.

         IN WITNESS WHEREOF, the parties have executed this Agreement as of the
day and year first above written.

                                       PRECEPT:

                                       PRECEPT BUSINESS SERVICES, INC.

                                       By:
                                          --------------------------------------
                                       Printed Name:
                                                    ----------------------------
                                       Title:
                                             -----------------------------------



ACCEPTED as of this _____ day
of ____________________, 2000:



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DARWIN DEASON


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