EXHIBIT 1 --------- JOINT FILING AGREEMENT This will confirm the agreement by and among all the undersigned that the Schedule 13G filed on or about this date with respect to the beneficial ownership of the undersigned of shares of the Common Stock,...

                                                                       EXHIBIT 1
                                                                       ---------





                             JOINT FILING AGREEMENT

                  This will confirm the agreement by and among all the
undersigned that the Schedule 13G filed on or about this date with respect to
the beneficial ownership of the undersigned of shares of the Common Stock, par
value $.01 per share, of Aether System, Inc. is being filed on behalf of each of
the undersigned. This agreement may be executed in two or more counterparts,
each of which shall be deemed an original, but all of which together shall
constitute one and the same instrument.



Dated: September 6, 2000.
       -----------
                                   REUTERS GROUP PLC


                                   By:    /s/ R.E.S. Xxxxxx
                                      -----------------------
                                   Name:  R.E.S. Xxxxxx
                                   Title: Secretary

                                   REUTERS MARKET CLIP HOLDINGS SARL


                                   By:    /s/  Xxx Xxxxxxxx
                                      -----------------------
                                   Name:  Xxx Xxxxxxxx
                                   Title: Director


                                   REUTERS HOLDINGS SWITZERLAND SA


                                   By:    /s/  Xxx Xxxxxxxx
                                      -----------------------
                                   Name:  Xxx Xxxxxxxx
                                   Title: Director:



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                                   REUTERS OVERSEAS HOLDINGS BV


                                   By:    /s/  T.A.M. Hakvoort
                                      --------------------------
                                   Name:  T.A.M. Hakvoort
                                   Title: Director


                                   REUTERS GROUP OVERSEAS HOLDINGS (UK)
                                   LIMITED


                                   By:    /s/ R.E.S. Xxxxxx
                                      -----------------------
                                   Name:  R.E.S. Xxxxxx
                                   Title: Secretary




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