Environment Variable from a form.

Hey Gurus,

   Does anyone throw some light into how I can set the UNIX envrironment variables from within a form. I am trying to do something like

   command1 := 'setenv ORACLE_HOME $ORACLE_HOMEDB';

within the code of the button. Can anybody tell me what if anything I am doing wrong. Attached is a file with the full code of the form . Please tell me if I am doing something wrong.

                                        Tapan H Trivedi