I think it has to be IVR. In any VM you wouldn't have enough buttons to cover all possible area codes unless there are not more then 8 or 9. In that scenario you can create Routing manue 1 & 2 and each area code would correspond to apropriate respond. You would have to create virtual mailboxes that would match area codes. let say you have 519, 520 & 521 area codes. I would create 3 Routing mailboxes: 519,520 & 521 with apropriate Greetings in each. After customer dial any of those area codes I would say: " Please dial 1....9 for assistance and send a call outside or iside. I think it might work.