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                                                             Exhibit 99.906.Cert

FORM N-CSR/A ITEM 11(b) EXHIBIT

                            CERTIFICATION PURSUANT TO
                             18 U.S.C. SECTION 1350,
                             AS ADOPTED PURSUANT TO
                  SECTION 906 OF THE SARBANES-OXLEY ACT OF 2002

        The undersigned hereby certify in their capacity as Treasurer and
President, respectively, of Eaton Vance Mutual Funds Trust (the "Trust") (on
behalf of Eaton Vance Municipal Bond Fund), that:

 (a) the Annual Report of the Trust (on behalf of Eaton Vance Municipal Bond
     Fund) on Form N-CSR/A for the period ended December 31, 2003 (the "Report")
     fully complies with the requirements of Section 13(a) or 15(d) of the
     Securities Exchange Act of 1934, as amended; and

 (b) the information contained in the Report fairly presents, in all material
     respects, the financial condition and the results of operations of the
     Trust (on behalf of Eaton Vance Municipal Bond Fund) for such period.

A SIGNED ORIGINAL OF THIS WRITTEN STATEMENT REQUIRED BY SECTION 906 HAS BEEN
PROVIDED TO THE TRUST AND WILL BE RETAINED BY THE TRUST AND FURNISHED TO THE
SECURITIES AND EXCHANGE COMMISSION OR ITS STAFF UPON REQUEST.


Eaton Vance Mutual Funds Trust (On behalf of Eaton Vance Municipal Bond Fund)

Date: June 8, 2004
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/S/ James L. O'Connor
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James L. O'Connor
Treasurer

Date: June 8, 2004


/S/ Thomas E. Faust Jr.
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Thomas E. Faust Jr.
President