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                                                                    EXHIBIT 10.4

                              BANK ONE, MICHIGAN               TEL  248 816 0233
                              MI1 8923                         FAX  248 816 0254
                              2155 W. BIG BEAVER
                              TROY, MICHIGAN 48084-3422

[BANK ONE LOGO]

September 13, 1999

Mr. R.S. Ramdas
Sr. Director Internal Audit, Tax & Treasury
Syntel, Inc.
2800 Livernois
Suite 400
Troy, MI 48083

Dear Ramdas:

 I am pleased to inform you that Bank One, Michigan has extended and increased
 the Uncommitted Credit Authorizations described in Section 1.1 of the Credit
 Authorization Agreement, executed by you and the Bank on September 18, 1998.
 As referenced in Section 1.1, Facility A has been increased to $40,000,000 and
 Facility B has been increased to $20,000,000.  The expiration date set forth in
 Section 1.1 of the Credit Authorization Agreement for Facilities A and B is
 changed to August 31, 2000.  As referenced in Section 6.3 F of the Credit
 Authorization Agreement, the Tangible Net Worth covenant shall not be permitted
 to be less than $45,000,000 (formerly $35,000,000).

 Except as modified by this letter, all of the terms and conditions of the
 Credit Authorization Agreement remain in effect. Please have Bharat Desai sign
 below to confirm this change.

 Sincerely,

 Bank One, Michigan

 By: /s/ Sarah C. McCoy
    --------------------
         Sarah C. McCoy

 Its:    Loan Officer
     -------------------
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[BANK ONE LOGO]

Accepted and Agreed to on this 25th day of OCTOBER, 1999.

SYNTEL, INC.

By: /s/ Bharat Desai
   ---------------------
        Bharat Desai

Its:     President
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                                                                   EXHIBIT 10.23

                             AMENDMENT NO. 3 TO THE
                      AMENDED AND RESTATED CREDIT AGREEMENT

                          Dated as of December 27, 1999

                  AMENDMENT NO. 3 TO THE AMENDED AND RESTATED CREDIT AGREEMENT
among Penda Corporation, a Florida corporation (the "Borrower"), the Lenders and
Banque Nationale de Paris, as Agent (the "Agent") for the Lenders.

                  PRELIMINARY STATEMENTS:

                  (1)  The Borrower, the Lenders and the Agent have entered into
an Amended and Restated Credit Agreement dated as of July 14, 1995 (as amended,
supplemented or otherwise modified through the date hereof, the "Credit
Agreement"). Capitalized terms not otherwise defined in this Amendment have the
same meanings as specified in the Credit Agreement.

                  (2)  The Borrower and the Required Lenders have agreed to
amend the Credit Agreement as hereinafter set forth.

                  SECTION 1. Amendments to Credit Agreement. The Credit
Agreement is, effective as of the date hereof and subject to the satisfaction of
the conditions precedent set forth in Section 2, hereby amended by inserting a
new subsection 5.02(b)(i)(E) to read as follows:

                  "(E) other unsecured Debt in an aggregate amount not to exceed
$1,200,000 at any time outstanding;".

                  SECTION 2. Conditions of Effectiveness. This Amendment shall
become effective on and as of the first date (the "Effective Date") on which the
Agent shall have received, in form and substance satisfactory to the Agent and
in sufficient copies for each Lender Party, counterparts of this Amendment
executed by the Borrower and all the Lenders or, as to any of the Lenders,
advice satisfactory to the Agent that such Lender has executed this Amendment
and the consent attached hereto executed by Tri-Glas.

                  SECTION 3. Representations and Warranties of the Borrower.

                  (a)  The Borrower represents and warrants as follows:

                  (i)    Each of the Borrower and Tri-Glas is a corporation duly
         organized, validly existing and in good standing under the laws of the
         jurisdiction of its organization.

                  (ii)   The execution, delivery and performance by the Borrower
         of this Amendment and by Tri-Glas of the consent attached hereto and
         the consummation of the transactions contemplated hereby, is within its
         corporate powers, has been duly authorized by all necessary corporate
         action and does not contravene (1) its charter or by-laws; or (2) any
         law or any contractual restriction binding on or affecting it.

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                  (iii)  No authorization or approval or other action by, and no
         notice to or filing with, any governmental authority or regulatory body
         or any other third party is required for the due execution, delivery,
         recordation, filing or performance by the Borrower of this Amendment
         and by Tri-Glas of the consent attached hereto.

                  (iv)   This Amendment has been duly executed and delivered by
         the Borrower. This Amendment is the legal, valid and binding
         obligations of the Borrower, enforceable against the Borrower in
         accordance with its terms.

                  (v)    The consent attached hereto has been duly executed and
         delivered by Tri-Glas. The consent attached hereto is the legal, valid
         and binding obligations of Tri-Glas, enforceable against Tri-Glas in
         accordance with its terms.

                  (b)    The Borrower hereby repeats the representations and
         warranties contained in each Loan Document as if made on the date of
         this Amendment, other than any such representations or warranties that,
         by their terms, refer to a specific date other than the date of this
         Amendment, in which case as of such specific date.

                  SECTION 4. Reference to and Effect on the Loan Documents. (a)
On and after the effectiveness of this Amendment, each reference in the Credit
Agreement to "this Agreement", "hereunder", "hereof" or words of like import
referring to the Credit Agreement, and each reference in each of the other Loan
Documents to "the Credit Agreement", "thereunder", "thereof" or words of like
import referring to the Credit Agreement, shall mean and be a reference to the
Credit Agreement, as amended by this Amendment.

         (b)      The Credit Agreement and each of the other Loan Documents, as
specifically amended by this Amendment, are and shall continue to be in full
force and effect and are hereby in all respects ratified and confirmed. Without
limiting the generality of the foregoing, the Collateral Documents and all of
the Collateral described therein do and shall continue to secure the payment of
all Obligations of the Loan Parties under the Loan Documents, in each case as
amended by this Amendment.

         (c)      The execution, delivery and effectiveness of this Amendment
shall not, except as expressly provided herein, operate as a waiver of any
right, power or remedy of any Lender or the Agent under any of the Loan
Documents, nor constitute a waiver of any provision of any of the Loan
Documents.

                  SECTION 5. Costs, Expenses. The Borrower agrees to pay on
demand all costs and expenses of the Agent in connection with the preparation,
execution, delivery and administration, modification and amendment of this
Amendment and the other instruments and documents to be delivered hereunder
(including, without limitation, the reasonable fees and expenses of counsel for
the Agent) in accordance with the terms of Section 8.04 of the Credit Agreement.

                  SECTION 6. Execution in Counterparts. This Amendment may be
executed in any number of counterparts and by different parties hereto in
separate counterparts, each of which when so executed shall be deemed to be an
original and all of which taken together shall constitute but one and the same
agreement. Delivery of an executed counterpart of a signature page to this
Amendment by telecopier shall be effective as delivery of a manually executed
counterpart of this Amendment.

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                  SECTION 7.  Governing Law.  This Amendment shall be governed
by, and construed in accordance with, the laws of the State of New York.

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                  IN WITNESS WHEREOF, the parties hereto have caused this
Amendment to be executed by their respective officers thereunto duly authorized,
as of the date first above written.

                                       PENDA CORPORATION

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

                                       BANQUE NATIONAL DE PARIS,

                                         as Agent and as Lender

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

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

                                       FIRSTAR BANK MILWAUKEE, N.A.

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

                                     CONSENT

                                       Dated as of December 27, 1999

         The undersigned, Tri-Glas Corporation, an Alabama corporation, as
Guarantor under the Subsidiaries Guaranty dated July 15, 1995 (the "Guaranty")
in favor of the Agent, for its benefit and the benefit of the Lenders Parties
party to the Credit Agreement referred to in the foregoing Amendment, hereby
consents to such Amendment and hereby confirms and agrees that (a)
notwithstanding the effectiveness of such Amendment, the Guaranty is, and shall
continue to be, in full force and effect and is hereby ratified and confirmed in
all respects, except that, on and after the effectiveness of such Amendment,
each reference in the Guaranty to the "Credit Agreement", "thereunder",
"thereof" or words of like import shall mean and be a reference to the Credit
Agreement, as amended by such Amendment, and (b) the Collateral Documents to
which such Grantor is a party and all of the Collateral described therein do,
and shall continue to, secure the payment of all of the Secured Obligations (in
each case, as defined therein).

                                        TRI-GLAS CORPORATION

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

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