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                                                                   EXHIBIT 10.15



                       FIRST AMENDMENT TO CREDIT AGREEMENT

          THIS FIRST AMENDMENT TO CREDIT AGREEMENT ("Amendment"), dated
effective as of January 15, 2001 (the "Amendment Date"), is among
INTERVOICE-BRITE, INC. (formerly InterVoice, Inc.; "Parent"), BRITE VOICE
SYSTEMS, INC. (successor by merger to InterVoice Acquisition Subsidiary III,
Inc.; "Borrower"), BANK OF AMERICA, NATIONAL ASSOCIATION (successor by merger to
Bank of America National Trust and Savings Association) in its capacity as
administrative agent ("Agent"), and the Lenders party hereto.

                                    RECITALS:

          A. Parent, Borrower, Agent, and the Lenders have entered into that
certain Credit Agreement dated as of June 1, 1999 (the "Credit Agreement").
Borrower has requested that certain provisions of the Credit Agreement be
amended in certain respects.

          B. Subject to satisfaction of the conditions set forth herein, Agent
and the Lenders are willing to amend the Credit Agreement as specifically
provided herein.

          NOW, THEREFORE, BE IT RESOLVED, THAT, in consideration of the premises
herein contained and other good and valuable consideration, the receipt and
sufficiency of which are hereby acknowledged, the parties hereto hereby agree as
follows:


                                    ARTICLE 1

                                   Definitions

          Section 1.1 Definitions. Capitalized terms used in this Amendment, to
the extent not otherwise defined herein, shall have the same meanings as in the
Credit Agreement, as amended hereby.


                                    ARTICLE 2

                                    Amendment

          Section 2.1 Amendment to Section 10.1(b). Effective as of the
Amendment Date, Section 10.1(b) of the Credit Agreement is hereby amended by
adding thereto, immediately following the semicolon at the end thereof, a
proviso which shall read in its entirety as follows:

          provided that with respect to such financial report for the Fiscal
          Quarter ending November 30, 2000, such financial report shall be
          delivered by February 2, 2001;

          Section 2.2 Amendment to Section 10.1(c). Effective as of the
Amendment Date, Section 10.1(c) of the Credit Agreement is hereby amended and
restated to read in its entirety as follows:



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                   (c) Compliance Certificate. As soon as available, and in any
          event accompanying the financial statements delivered in accordance
          with Section 10.1(a) and Section 10.1(b), a Compliance Certificate,
          together with schedules setting forth the calculations supporting the
          computations therein, and as soon as available, and in any event on or
          before April 30, 2001, a Compliance Certificate certifying as to the
          Fixed Charge Coverage Ratio of Parent as of the month ending March 31,
          2001 together with schedules and other information as may be
          reasonably requested by the Agent setting forth the calculations
          supporting the computations therein.

          Section 2.3 Amendment to Section 12.2. Effective as of the Amendment
Date, Section 12.2 of the Credit Agreement is hereby amended and restated to
read in its entirety as follows:

                   Section 12.2 Fixed Charge Coverage Ratio. As of the end of
          the month ending March 31, 2001 and as of the end of each Fiscal
          Quarter ending thereafter, Parent shall not permit the Fixed Charge
          Coverage Ratio, calculated as of the end of such month or Fiscal
          Quarter, as applicable, for the preceding twelve (12) month period
          then ending, to be less than 1.25 to 1.00.


                                    ARTICLE 3

                                   Conditions

         Section 3.1 Conditions Precedent. The effectiveness of this Amendment
is subject to the satisfaction of the following conditions precedent:

                   (a) the representations and warranties contained herein and
          in all other Loan Documents, as amended hereby, shall be true and
          correct in all material respects as of the date hereof as if made on
          the date hereof, except for such representations and warranties
          limited by their terms to a specific date;

                   (b) after giving effect to Article 2 hereof, no Default or
          Event of Default shall have occurred and be continuing;

                   (c) Borrower and each Lender shall have delivered to Agent an
          executed original copy of this Amendment;

                   (d) Borrower shall have paid to Agent all fees, costs, and
          expenses owed to and/or incurred by each of Agent and each such Lender
          arising in connection with the Credit Agreement or this Amendment,
          including, without limitation, the reasonable fees, costs, and
          expenses of Agent's legal counsel, Jenkens & Gilchrist, a Professional
          Corporation; and

                   (e) all proceedings taken in connection with the transactions
          contemplated by this Amendment and all documentation and other legal
          matters incident thereto shall be



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          satisfactory to (i) Agent, (ii) the Lenders, and (iii) Agent's legal
          counsel, Jenkens & Gilchrist, a Professional Corporation.


                                    ARTICLE 4

                  Ratifications, Representations and Warranties

          Section 4.1 Ratifications. The terms and provisions set forth in this
Amendment shall modify and supersede all inconsistent terms and provisions set
forth in the Credit Agreement and, except as expressly modified and superseded
by this Amendment, the terms and provisions of the Credit Agreement and the
other Loan Documents are ratified and confirmed and shall continue in full force
and effect. Parent, Borrower, Agent, and the Lenders agree that the Credit
Agreement as amended hereby and the other Loan Documents shall continue to be
legal, valid, binding, and enforceable in accordance with their respective
terms.

          Section 4.2 Representations and Warranties. Each of Parent and
Borrower hereby represents and warrants to Agent and the Lenders that (a) the
execution, delivery, and performance of this Amendment and any and all other
Loan Documents executed and/or delivered in connection herewith have been
authorized by all requisite action on the part of Parent and Borrower and will
not violate the articles of incorporation or bylaws of Parent or Borrower, (b)
the representations and warranties contained in the Credit Agreement, as amended
hereby, and any other Loan Document are true and correct on and as of the date
hereof as though made on and as of the date hereof (except to the extent that
such representations and warranties were expressly, in the Credit Agreement,
made only in reference to a specific date), (c) after giving effect to this
Amendment, no Default or Event of Default has occurred and is continuing, and
(d) each of Parent and Borrower is in full compliance with all covenants and
agreements contained in the Credit Agreement, as amended hereby, and the other
Loan Documents.


                                    ARTICLE 5

                                  Miscellaneous

          Section 5.1 Survival of Representations and Warranties. All
representations and warranties made in this Amendment or any other Loan Document
including any Loan Document furnished in connection with this Amendment shall
survive the execution and delivery of this Amendment and the other Loan
Documents, and no investigation by Agent or any Lender shall affect the
representations and warranties or the right of Agent or any Lender to rely upon
them.

          Section 5.2 Reference to Credit Agreement. Each of the Loan Documents,
including the Credit Agreement and any and all other agreements, documents, or
instruments now or hereafter executed and delivered pursuant to the terms hereof
or pursuant to the terms of the Credit Agreement as amended hereby, are hereby
amended so that any reference in such Loan Documents to the Credit Agreement
shall mean a reference to the Credit Agreement as amended hereby.



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          Section 5.3 Severability. Any provision of this Amendment held by a
court of competent jurisdiction to be invalid or unenforceable shall not impair
or invalidate the remainder of this Amendment and the effect thereof shall be
confined to the provision so held to be invalid or unenforceable.

          Section 5.4 Applicable Law. THIS AMENDMENT SHALL BE GOVERNED BY AND
CONSTRUED IN ACCORDANCE WITH THE LAWS OF THE STATE OF TEXAS AND THE APPLICABLE
LAWS OF THE UNITED STATES OF AMERICA.

          Section 5.5 Successors and Assigns. This Amendment is binding upon and
shall inure to the benefit of Parent, Borrower, Agent, and the Lenders and their
respective successors and assigns, except neither Parent nor Borrower may assign
or transfer any of its respective rights or obligations hereunder without the
prior written consent of the Lenders.

          Section 5.6 Counterparts. This Amendment may be executed in one or
more counterparts, and on telecopy counterparts each of which when so executed
shall be deemed to be an original, but all of which when taken together shall
constitute one and the same agreement.

          Section 5.7 Effect of Amendment. No consent or waiver, express or
implied, by Agent or any Lender to or for any breach of or deviation from any
covenant, condition, or duty by Parent, Borrower, or any other Loan Party shall
be deemed a consent or waiver to or of any other breach of the same or any other
covenant, condition, or duty.

          Section 5.8 Headings. The headings, captions, and arrangements used in
this Amendment are for convenience only and shall not affect the interpretation
of this Amendment.

          Section 5.9 Entire Agreement. THIS AMENDMENT AND ALL OTHER
INSTRUMENTS, DOCUMENTS, AND AGREEMENTS EXECUTED AND DELIVERED IN CONNECTION WITH
THIS AMENDMENT EMBODY THE FINAL, ENTIRE AGREEMENT AMONG THE PARTIES HERETO AND
SUPERSEDE ANY AND ALL PRIOR COMMITMENTS, AGREEMENTS, REPRESENTATIONS, AND
UNDERSTANDINGS, WHETHER WRITTEN OR ORAL, RELATING TO THIS AMENDMENT, AND MAY NOT
BE CONTRADICTED OR VARIED BY EVIDENCE OF PRIOR, CONTEMPORANEOUS, OR SUBSEQUENT
ORAL AGREEMENTS OR DISCUSSIONS OF THE PARTIES HERETO. THERE ARE NO ORAL
AGREEMENTS AMONG THE PARTIES HERETO.

                  [remainder of page intentionally left blank]



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          IN WITNESS WHEREOF, the parties hereto have executed and delivered
this Amendment effective as of the date first written above.


                                   BORROWER

                                   BRITE VOICE SYSTEMS, INC. (successor
                                   by merger to InterVoice Acquisition
                                   Subsidiary III, Inc.)



                                   By:  /s/ ROB-ROY J. GRAHAM
                                      ------------------------------------------
                                   Name:    Rob-Roy J. Graham
                                        ----------------------------------------
                                   Title:   CFO
                                         ---------------------------------------



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                                   PARENT:

                                   INTERVOICE-BRITE, INC. (formerly
                                   InterVoice, Inc.)



                                   By:  /s/ ROB-ROY J. GRAHAM
                                      ------------------------------------------
                                   Name:    Rob-Roy J. Graham
                                        ----------------------------------------
                                   Title:   CFO
                                         ---------------------------------------



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                                   AGENT and ISSUING BANK:

                                   BANK OF AMERICA, NATIONAL ASSOCIATION
                                   (successor by merger to Bank of America
                                   National Trust and Savings Association), as
                                   Agent



                                   By:  /s/ FRED L. THORNE
                                      ------------------------------------------
                                   Name:    Fred L. Thorne
                                        ----------------------------------------
                                   Title:   Managing Director
                                         ---------------------------------------



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                                   LENDERS:

                                   BANK OF AMERICA, NATIONAL ASSOCIATION
                                   (successor by merger to Bank of America
                                   National Trust and Savings Association)



                                   By:  /s/ FRED L. THORNE
                                      ------------------------------------------
                                   Name:    Fred L. Thorne
                                        ----------------------------------------
                                   Title:   Managing Director
                                         ---------------------------------------



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                                   BANK ONE, TEXAS, N.A.



                                   By:  /s/ TIMOTHY A. SMITH
                                      ------------------------------------------
                                   Name:    Timothy A. Smith
                                        ----------------------------------------
                                   Title:   Vice President
                                         ---------------------------------------



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                                   U.S. BANK NATIONAL ASSOCIATION



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



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                                   FLEET NATIONAL BANK



                                   By:  /s/ DEBRA E. DELVECCHO
                                      ------------------------------------------
                                   Name:    Debra E. Delveccho
                                        ----------------------------------------
                                   Title:   Director
                                         ---------------------------------------



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                                   IBM CREDIT CORPORATION



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



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                                   UNION BANK OF CALIFORNIA, N.A.



                                   By:  /s/ JAMES B. GOUDY
                                      ------------------------------------------
                                   Name:    James B. Goudy
                                        ----------------------------------------
                                   Title:   Vice President
                                         ---------------------------------------



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                                   THE BANK OF NOVA SCOTIA



                                   By:  /s/ F.C.H. ASHBY
                                      ------------------------------------------
                                   Name:    F.C.H. Ashby
                                        ----------------------------------------
                                   Title: Senior Manager Loan Operations
                                         ---------------------------------------



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                                   BANKBOSTON, N.A.



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



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                                   BANK AUSTRIA CREDITANSTALT
                                   CORPORATE FINANCE, INC.



                                   By:  /s/ J. A. SEAY
                                      ------------------------------------------
                                   Name:    J. A. Seay
                                        ----------------------------------------
                                   Title:   Vice President
                                         ---------------------------------------



                                   By:  /s/ CLIFFORD L. WELLS
                                      ------------------------------------------
                                   Name:    Clifford L. Wells
                                        ----------------------------------------
                                   Title:   Senior Vice President
                                         ---------------------------------------



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                                   COMERICA BANK



                                   By:  /s/ T. BANCROFT MATTEI
                                      ------------------------------------------
                                   Name:    T. Bancroft Mattei
                                        ----------------------------------------
                                   Title:   Account Officer
                                         ---------------------------------------



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           REAFFIRMATION OF GUARANTY AND PLEDGE AND SECURITY AGREEMENT



           Each of the undersigned hereby (a) consents to the execution and
delivery of the First Amendment to Credit Agreement to which this Reaffirmation
of Guaranty and Pledge and Security Agreement is attached (the "Amendment") by
the parties thereto, (b) that the Amendment shall not limit or diminish the
obligations of each of the undersigned under their certain Loan Documents
delivered in connection with the Credit Agreement, executed or joined in by each
of the undersigned and delivered to Agent, (c) reaffirms its obligations under
each of such Loan Documents, and (d) agrees that each of such Loan Documents
remains in full force and effect and is hereby ratified and confirmed.

Dated effective as of February 27, 2001.


                                   INTERVOICE GP, INC.


                                   By: /s/ ROB-ROY J. GRAHAM
                                      ------------------------------------------
                                   Name:   Rob-Roy J. Graham
                                        ----------------------------------------
                                   Title:  CFO
                                         ---------------------------------------


                                   INTERVOICE LP, INC.


                                   By: /s/ ROB-ROY J. GRAHAM
                                      ------------------------------------------
                                   Name:   Rob-Roy J. Graham
                                        ----------------------------------------
                                   Title:  CFO
                                         ---------------------------------------


                                   INTERVOICE ACQUISITION
                                   SUBSIDIARY, INC.


                                   By: /s/ ROB-ROY J. GRAHAM
                                      ------------------------------------------
                                   Name:   Rob-Roy J. Graham
                                        ----------------------------------------
                                   Title:  CFO
                                         ---------------------------------------



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                                   INTERVOICE ACQUISITION
                                   SUBSIDIARY II, INC.


                                   By: /s/ ROB-ROY J. GRAHAM
                                      ------------------------------------------
                                   Name:   Rob-Roy J. Graham
                                        ----------------------------------------
                                   Title:  CFO
                                         ---------------------------------------



                                   INTERVOICE LIMITED PARTNERSHIP


                                   By: InterVoice GP, Inc.


                                   By: /s/ ROB-ROY J. GRAHAM
                                      ------------------------------------------
                                   Name:   Rob-Roy J. Graham
                                        ----------------------------------------
                                   Title:  CFO
                                         ---------------------------------------



                                   BVSI, INC.


                                   By: /s/ ROB-ROY J. GRAHAM
                                      ------------------------------------------
                                   Name:   Rob-Roy J. Graham
                                        ----------------------------------------
                                   Title:  CFO
                                         ---------------------------------------



                                   BVS INVESTCO, INC.


                                   By: /s/ ROB-ROY J. GRAHAM
                                      ------------------------------------------
                                   Name:   Rob-Roy J. Graham
                                        ----------------------------------------
                                   Title:  CFO
                                         ---------------------------------------



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