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                                                                   EXHIBIT 10.62

                               SECOND AMENDMENT
                                      TO
                             AMENDED AND RESTATED
                          REVOLVING CREDIT AGREEMENT

     Second Amendment dated as of September 30, 1999 to Amended and Restated
Revolving Credit Agreement (the "Second Amendment"), by and among TIER
TECHNOLOGIES, INC., a California corporation (the "Company"), TIER TECHNOLOGIES
(UNITED KINGDOM), INC., a Delaware corporation ("Tier UK" and, collectively with
the Company, the "Borrowers" and each individually, a "Borrower") and
BANKBOSTON, N.A. (the "Bank"), amending certain provisions of the Amended and
Restated Revolving Credit Agreement dated as of May 28, 1999 (as amended and in
effect from time to time, the "Credit Agreement") by and among the Borrowers and
the Bank.  Terms not otherwise defined herein which are defined in the Credit
Agreement shall have the same respective meanings herein as therein.

     WHEREAS, the Borrowers and the Bank have agreed to modify certain terms and
conditions of the Credit Agreement as specifically set forth in this Second
Amendment;

     NOW, THEREFORE, in consideration of the premises and the mutual agreements
contained herein and for other good and valuable consideration, the receipt and
sufficiency of which are hereby acknowledged, the parties hereto hereby agree as
follows:

     (S)1.  Amendment to (S)1 of the Credit Agreement.  Section 1.1 of the
            -----------------------------------------
Credit Agreement is hereby amended by inserting the following definition in the
appropriate alphabetical order:

            St. George Facility. That certain loan facility in the
            -------------------
     aggregate principal amount of not more than $3,300,000 Australian
     Dollars provided from St. George Bank Limited to Tier Australia,
     such facility to be on substantially the terms set forth in the
     October 19, 1999 letter from St. George Bank Limited to Tier
     Australia, a copy of which has been provided to the Bank.

            Tier Australia.  As defined in Section 6.1(h).
            --------------

     (S)2.  Amendment to (S)5 of the Credit Agreement.  Section 5.8 of the
            -----------------------------------------
Credit Agreement is hereby amended by deleting the amount "$3,400,000" which
appears in subparagraph (b) of Section 5.8 and substituting in place thereof the
amount "$2,900,000".

     (S)3.  Amendment to Section 6 of the Credit Agreement.  Section 6 of the
            ----------------------------------------------
Credit Agreement is hereby amended as follows:
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                                      -2-

          (a)  Section 6.1(g) of the Credit Agreement is hereby amended by (i)
     deleting the words "Indebtedness of a Foreign Subsidiary to the Company in
     the form of" which appear in Section 6.1(g) and substituting in place
     thereof the words "Indebtedness of a Foreign Subsidiary, other than Tier
     Australia, to the Company in the form of"; (ii) deleting the words "the
     Foreign Subsidiary" which appear in Section 6.1(g)(iv) and substituting in
     place thereof the words "such Foreign Subsidiary"; and (iii) deleting the
     amount "$3,000,000" which appears in Section 6.1(g)(v) and substituting in
     place thereof the amount "$2,000,000".

          (b)  Section 6.1(h) of the Credit Agreement is hereby amended by (i)
     deleting the text of Section 6.1(h)(ii) in its entirety and substituting in
     place thereof the words "(ii) the aggregate principal amount of such loan
     does not exceed the lesser of (1) $1,000,000 and (2) an amount equal to (A)
     the aggregate purchase price for the assets of Simsion & Bowles Pty Ltd. to
     be acquired by Tier Australia on or prior to December 31, 1999 (the "S&B
     Acquisition") less (B) the aggregate principal amount of the St. George
                   ----
     Facility used to finance the S&B Acquisition"; and (ii) deleting the date
     "September 28, 1999" which appears in Section 6.1(h)(iii) and substituting
     in place thereof the date "November 30, 1999".

          (c)  Section 6.1(i) of the Credit Agreement is hereby amended by
     deleting the word "and" which appears at the end of Section 6.1(i).

          (d)  Section 6.1(j) of the Credit Agreement is hereby amended by
     deleting the period which appears at the end of Section 6.1(j) and
     substituting in place thereof a semicolon and the word "and".

          (e)  Section 6.1 of the Credit Agreement is amended by inserting
     immediately after the text of Section 6.1(j) the following:

          (k)  Indebtedness of Tier Australia to St. George Bank Limited
     pursuant to the St. George Facility.

          (f)  Section 6.5 of the Credit Agreement is hereby amended by (i)
     deleting the word "and" which appears at the end of Section 6.5(e); (ii)
     deleting the period which appears at the end of Section 6.5(f) and
     substituting in place thereof a semicolon and the word "and"; and (iii)
     inserting immediately at the end of Section 6.5(f) the following:

               (g)  liens in favor of St. George Bank Limited on the assets of
          Tier Australia to secure the Indebtedness permitted by Section 6.1(k).

          (g)  Section 6.10 of the Credit Agreement is hereby amended by (i)
     inserting immediately after the words "Foreign Subsidiaries" which appears
     in Section 6.10(ii) the words "other than Tier Australia"; and (ii)
     deleting the text of Section 6.10(iii) in its entirety and restating it as
     follows:
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                                      -3-

            (iii)  Investments by the Company in Tier Australia with respect to
            Indebtedness permitted by Section 6.1(h) hereof so long as (1) Tier
            Australia remains a Subsidiary of the Company; (2) no Default or
            Event of Default has occurred and is continuing; (3) the aggregate
            amount of the Investment does not exceed the amount set forth in
            Section 6.1(h)(ii); (4) such Investment is made not later than
            November 30, 1999; (5) the proceeds of such Investment are used by
            Tier Australia to consummate the S&B Acquisition; and (6) such
            Investment is not made prior to the date of consummating the S&B
            Acquisition;

     (S)4.  Conditions to Effectiveness.  This Second Amendment shall not become
            ---------------------------
effective until the Bank receives the following:

            (a)  a counterpart of this Second Amendment, executed by the
     Borrowers and the Banks; and

            (b)  payment in cash of an amendment fee of $8,000 for the account
     of the Bank.

     (S)5.  Representations and Warranties.  The Borrowers hereby repeat, on and
            ------------------------------
as of the date hereof, each of the representations and warranties made by them
in (S)4 of the Credit Agreement, and such representations and warranties remain
true as of the date hereof (except to the extent of changes resulting from
transactions contemplated or permitted by the Credit Agreement and the other
Loan Documents and changes occurring in the ordinary course of business that
singly or in the aggregate are not materially adverse, and to the extent that
such representations and warranties relate expressly to an earlier date),
provided, that all references therein to the Credit Agreement shall refer to
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such Credit Agreement as amended hereby.  In addition, each Borrower hereby
represents and warrants that the execution and delivery by each Borrower and its
Subsidiaries of this Second Amendment and the performance by such Borrower and
its Subsidiaries of all of its agreements and obligations under the Credit
Agreement as amended hereby and the other Loan Documents are within the
corporate authority of each such Borrower and its Subsidiaries and has been duly
authorized by all necessary corporate action on the part of such Borrower and
its Subsidiaries.

     (S)6.  Ratification, Etc.  Except as expressly amended hereby, the Credit
            -----------------
Agreement, the Security Documents and all documents, instruments and agreements
related thereto are hereby ratified and confirmed in all respects and shall
continue in full force and effect.  The Credit Agreement and this Second
Amendment shall be read and construed as a single agreement.  All references in
the Credit Agreement or any related agreement or instrument to the Credit
Agreement shall hereafter refer to the Credit Agreement as amended hereby.

     (S)7.  No Waiver.  Nothing contained herein shall constitute a waiver of,
            ---------
impair or otherwise affect any Obligations, any other obligation of the
Borrowers or any rights of the Bank consequent thereon.
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     (S)8.  Counterparts.  This Second Amendment may be executed in one or more
            ------------
counterparts, each of which shall be deemed an original but which together shall
constitute one and the same instrument.

     (S)9.  Governing Law.  THIS SECOND AMENDMENT SHALL BE GOVERNED BY, AND
            -------------
CONSTRUED IN ACCORDANCE WITH, THE LAWS OF THE COMMONWEALTH OF MASSACHUSETTS
(WITHOUT REFERENCE TO CONFLICT OF LAWS).
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     IN WITNESS WHEREOF, the parties hereto have executed this Second Amendment
as a document under seal as of the date first above written.

                                        TIER TECHNOLOGIES, INC.



                                        By: /s/ G.K. Ross
                                            -------------
                                        Title: EVP & CFO

                                        TIER TECHNOLOGIES
                                         (UNITED KINGDOM), INC.



                                        By: /s/ G.K. Ross
                                            -------------
                                        Title: Director

                                        BANKBOSTON, N.A.



                                        By: /s/ illegible
                                            -------------
                                        Title: Vice President