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                                                                    EXHIBIT 31.2

                        SARBANES-OXLEY 302 CERTIFICATION

I, David A. Feste, Chief Financial Officer of Datakey, Inc., certify that:

     1.  I have reviewed this report on Form 10-KSB of Datakey, Inc.;

     2.  Based on my knowledge, this 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 report;

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

     4.  The small business issuer's other certifying officer 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 small business issuer and 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
              small business issuer, including its consolidated subsidiaries, is
              made known to us by others within those entities, particularly
              during the period in which this report is being prepared;

              (b) Evaluated the effectiveness of the small business issuer'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 small business
              issuer's internal control over financial reporting that occurred
              during the small business issuer's most recent fiscal quarter (the
              small business issuer's fourth fiscal quarter in the case of an
              annual report) that has materially affected, or is reasonably
              likely to materially affect, the small business issuer's internal
              control over financial reporting; and

     5.  The small business issuer's other certifying officer and I have
         disclosed, based on our most recent evaluation of internal control over
         financial reporting, to the small business issuer's auditors and the
         audit committee of the small business issuer's board of directors (or
         persons performing the equivalent functions):

              (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 small business
              issuer'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 small
              business issuer's internal control over financial reporting.

Date: March 29, 2004

                          Signature:     /s/David A. Feste
                                         David A. Feste
                                         Chief Financial Officer