When you chose these "nonexistant" numbers - where did you pick thme from? You should use/renumber actual unequipped adjunct extention numbers for these mailboxes. Did you also include these "phantom" extention numbers in your voicemail cover group (usually 30)? What class of service did you assign to these voicemail boxes?
A second alternative with the older voicemail module - is to make them class of service 18 (general mailboxes). That way an outside caller using the AA to dial the extention will go right to the voicemail box. The salespeople can check there mail, by pressing *7 when the AA answers and then dial their mailbox number. They can access them internally by dialing voicemail and then entering the mailbox ext number.
Tom Daugirdas,
President
STCG, Inc.
stcg.com