Nevermind, I found the answer on the wiki:
Want to run an external program whenever a caller leaves a voice mail
message for a user? This is where the externnotify command comes in
handy. Externnotify takes a string value which is the command line
you want to execute when the caller
I have googled and can seem to find the answer to this one Does
anyone here have experience with externnotify in voicemail.conf?
The sample states that it will run when a message is delivered and
retrieved.
Does asterisk pass any arguments to the script?
Thanks.
Forrest Beck