Ditech Networks (DITC) 10-K 2004 FY Annual report

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Exhibit 32.1

CERTIFICATION OF CHIEF EXECUTIVE OFFICER AND CHIEF FINANCIAL OFFICER

        Pursuant to the requirement set forth in Rule 13a-14(b) of the Securities Exchange Act of 1934, as amended (the "Exchange Act"), and Section 1350 of Chapter 63 of Title 18 of the United States Code (18 U.S.C. § 1350), Timothy K. Montgomery, Chief Executive Officer of Ditech Communications Corporation (the "Company"), and William J. Tamblyn, the Chief Financial Officer of the Company, each hereby certify that, to the best of his knowledge:

1.

The Company's Annual Report on Form 10-K for the period ended April 30, 2004, and to which this Certification is attached as Exhibit 32.1, (the "Periodic Report") fully complies with the requirements of Section 13(a) or Section 15(d) of the Securities Exchange Act of 1934, and



2.

The information contained in the Periodic Report fairly presents, in all material respects, the financial condition and results of operations of the Company.

        IN WITNESS WHEREOF, the undersigned have set their hands hereto as of the 13^th Day of July, 2004.

/s/  TIMOTHY K. MONTGOMERY      Timothy K. Montgomery
CHIEF EXECUTIVE OFFICER

/s/  WILLIAM J. TAMBLYN      William J. Tamblyn
CHIEF FINANCIAL OFFICER

        The foregoing certification is not filed with the Securities and Exchange Commission as part of the Form 10-K or as a separate disclosure document and is not incorporated by reference into any filing of the Company under the Securities Act of 1933, as amended, or the Securities Exchange Act of 1934, as amended (whether made before or after the date of the Form 10-K), irrespectively of any general incorporation language contained in such filing.

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Exhibit 32.1