Ed, are you talking about 999 seconds of greeting length or actual message length? If you are talking about greeting length then would it be possible to record the greeting in a menu (that may have a registry item that could be extended) and time out into the mailbox if they need to leave a message? Just a thought, but it kind of sounds like maybe they are using the mailbox to record actual phone calls, which would mean this is no help at all.

"I thought I was wrong once, but I was mistaken"