Hello. We have a 3X8 Nortel phone system with M3710 phones. We recently switched to using our phone companies voicemail service rather than the Nortel systems built in message center (so that customers could reach our voicemail instead of a busy signal if we were on the line). The problem is that we no longer receive a notification of a new voicemail on our phones (the only notification is the quick beeping dial tone when we try to make a call). Is there a way to activate a notification for external voicemail providers like this? Thank you for your time.