Exhibit 32.1

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

     I, Jeffrey A. Leddy, Chief Executive Officer and President of SkyTerra
Communications, Inc. (the "Company"), hereby certifies, pursuant to 18 U.S.C.
Section 1350, as adopted pursuant to Section 906 of the Sarbanes-Oxley Act of
2002, that, to my knowledge:

     (1)      The Company's Annual Report on Form 10-K for the year ended
              December 31, 2003, as filed with the Securities and Exchange
              Commission on the date hereof (the "Report"), fully complies
              with the requirements of Section 13(a) or 15(d) of the
              Securities Exchange Act of 1934; and

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


                           By:   /s/ JEFFREY A. LEDDY
                                 ----------------------------------
                                 Name:  Jeffrey A. Leddy
                                 Title: Chief Executive Officer and President
                                        (Principal Executive Officer and
                                        Principal Financial Officer)
                                 Date:  March 29, 2004


     This certification accompanies the Report pursuant to Section 906 of the
Sarbanes-Oxley Act of 2002 and shall not be deemed filed by the Company for
purposes of Section 18 of the Securities Exchange Act of 1934, as amended.

     A signed original of this written statement required by Section 906, or
other document authenticating, acknowledging, or otherwise adopting the
signature that appears in typed form within the electronic version of this
written statement required by Section 906, has been provided to the Company
and will be retained by the Company and furnished to the Securities and
Exchange Commission or its staff upon request.