What ntozier is saying, is that there is no admin/staff interface to do things like this. Each "Ticket" is logically separate from each other, there is no concept of "User" which you could apply this logic to. You would have to integrate it with some other application.
If you are happy with simply "adding a box" to the staff ticket-view page, then (if it was me), I'd add some jQuery to AJAX the request back to the server and then simply "process it yourself", in whatever system you like. You could add the email address and ticket id to the ajax request.
