In PoliteMail versions 4.95+, a user can specify a different inbox for bounces to be returned to. Using this method, you can keep one sending account free from any undeliverables, and use a separate sending account to monitor bounces.
Open a New Message in PoliteMail. Under the PoliteMail flag pull-down menu, choose Return Path.
Now specify which email address from your Global Address Book you'd like the bounces to be returned to. Check Set as default if you always want bounces to go to this address.
This message will now be sent from the Communications' inbox with all bounces being returned to Alfred Pennyworth's inbox.