I have a scenario upcoming where I will have a few extensions that will not have a voicemail box associated with them. Instead if the call goes unanswered it will forward to the receptionist and, if left unanswered, will go into a GDM.
The receptionist will not have a personal voicemail box either. I would like to see that her phone gets a MWI light when there is a mesage in the GDM; is this possible?
This doesn't really answer your question, but in this scenario we utilize the email notification to alert there is a voicemail and include the attached voicemail in the email. We are sending this to a group since more than one person requires so this may not apply in your case.