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Exhibit 32.1 Section 1350 Certification

In connection with the filing of the Annual Report on Form 10-K for the Year
Ended December 31, 2003 (the "Report") by Cellular Technical Services Company,
Inc. ("Registrant"), each of the undersigned hereby certifies that:

     1.   The Report fully complies with the requirements of section 13(a) or
          15(d) of the Securities Exchange Act of 1934, as amended, and

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


               By: /s/ Stephen Katz
                   ----------------
               Stephen Katz
               Chief Executive Officer
               March 29, 2004


               By: /s/ Bruce R. York
                   -----------------
               Bruce R. York
               Vice President and Chief Financial Officer
               March 29, 2004

A signed original of this written statement required by Section 906of the
Sarbanes-Oxley Act of 2002 has been provided to Cellular Technical Services
Company, Inc and will be retained by the Registrant and furnished to the
Securities and Exchange Commission or its staff upon request.