I was just wondering if it was possible to view the extension or the full PSTN number? Reason being is we have "Click to Call" and this would be a great addition if we our users can reply to the message by calling the ext directly with C2C.
So you would have to customize the subject in Unity/Unity Connection. It depends on what version of Unity/Unity connection you have if you will have this option. Only the newer versions of the software allow you to make these changes.
In Unity Connection from the admin page on the left hand side under system settings click "Subject Line Formats". Here you can adjust what will be displayed for outside callers and inside callers.
For Unity in Web SA click configuration and then Message Subjects.
If you version doesn't have the above options, then you would need to upgrade to Unity 7/UC 7 or later to have this feature.
Unfortunately not. The voice mail is just an email message so the from address is going to be the name of the user it is sent from. The only thing that can be customized is the subject of the message.