Emailing Invoices

The Email settings for "From Name" and "From Email address" seem to be global. As our Customer Reps are responsible for customers in their region it would be great to be able to tie those two fields to the region where the customer is located. With the current constraints either one of the Reps has to take the lead and redistribute responses received or we have to use a "generic" email and give all the Reps access to the mailbox. Both scenarios are prone for manual error and overlooking emails needing attention.