1 EXHIBIT 21.1 SUBSIDIARIES OF WALL DATA INCORPORATED AS OF APRIL 30, 1998 STATE OF INCORPORATION OR COUNTRY IN WHICH SUBSIDIARY ORGANIZED -------------------------------------------- ------------------------ Wall Data (UK) Limited United Kingdom Wall Data (Canada) Limited Canada Wall Data (Barbados) Incorporated Barbados Wall Data France s.a.r.l. France Wall Data GmbH Germany Wall Data Australia Pty Ltd. Australia Wall Data Japan K.K. Japan Wall Data Mexico S.A. de C.V. Mexico Wall Data Asia Pte. Ltd. Singapore Wall Data Limited Ireland Wall Data International Delaware Wall Data do Brasil Limitada Brazil Software Development Tools Limited United Kingdom Software Development Tools Inc. Delaware Software Development Tools Inc. France France Expert Edge Computer Systems Limited Ireland Radisson Limited Ireland First Service Computer Dienstleistungs-GmbH, Germany Dietzenbach First Service Computer Dienstleistungs-GmbH, Germany Hattingen First Service Computer Dienstleistungs-GmbH, Germany Munchen