Hello Community,
I've used A@H/Trixbox for about two years at my home. It has bugged me for a while that I couldn't share the voicemail from the GUI (I manually patched the files to hard code the shared voicemail number). But now I finally took the time to implement it a little better.
What I did is add a field to the voicemail section on extentions. I added "Shared voicemail" which gets stored in the Asterisk DB (CLI->database->put AMPUSER/ext sharedvm). For example if your shared voicemail box (I created a CUSTOM extension for the shared vm) is 200 then for the extensions that should use the shared vm you put "200@default" into the shared vm field. You set the VM Status to disabled.
Incoming calls that timeout are then redirected to the shared VM box and context. *97 and *98 are directed to the shared voicemail as well.