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                                                                  Exhibit 31.1

                                 CERTIFICATION

I, Eleanor L. Thomas, certify that:

   1.  I have reviewed this quarterly report on Form 10-Q of Diversified Futures
       Trust I (the 'Trust');

   2.  Based on my knowledge, this quarterly report does not contain any untrue
       statement of a material fact or omit to state a material fact necessary
       to make the statements made, in light of the circumstances under which
       such statements were made, not misleading with respect to the period
       covered by this quarterly report;

   3.  Based on my knowledge, the financial statements, and other financial
       information included in this quarterly report, fairly present in all
       material respects the financial condition, results of operations and cash
       flows of the Trust as of, and for, the periods presented in this
       quarterly report;

   4.  The Trust's other certifying officers and I are responsible for
       establishing and maintaining disclosure controls and procedures (as
       defined in Exchange Act Rules 13a-15(e) and 15d-15(e)) for the Trust and
       we have:

        a)  designed such disclosure controls and procedures, or caused
            such disclosure controls and procedures to be designed under
            our supervision, to ensure that material information relating
            to the Trust, including its consolidated subsidiaries, is
            made known to us by others within those entities,
            particularly during the period in which this quarterly report
            is being prepared;

        b)  evaluated the effectiveness of the Trust's disclosure
            controls and procedures and presented in this report our
            conclusions about the effectiveness of the disclosure
            controls and procedures, as of the end of the period covered
            by this report based on such evaluation; and

        c)  disclosed in this report any change in the Trust's internal
            control over financial reporting that occurred during the
            Trust's most recent fiscal quarter that has materially
            affected, or is reasonably likely to materially affect, the
            Trust's internal control over financial reporting; and

   5.  The Trust's other certifying officers and I have disclosed, based on our
       most recent evaluation of internal control over financial reporting, to
       the Trust's auditors and the board of directors of the managing owner of
       the Trust:

        a)  all significant deficiencies and material weaknesses in the
            design or operation of internal control over financial
            reporting which are reasonably likely to adversely affect the
            Trust's ability to record, process, summarize and report
            financial information; and

        b)  any fraud, whether or not material, that involves management
            or other employees who have a significant role in the Trust's
            internal control over financial reporting.

Date:  August 14, 2003                 /s/ Eleanor L. Thomas
                                       --------------------------------------
                                       Eleanor L. Thomas
                                       President (chief executive officer)
                                         of the managing owner of the Trust