Multiple Collector Email Addresses

We have a scenario where we are collecting from two separate businesses. Our collectors have two different email accounts. In Advanced Collections, the IEX: SMTP FROM Profile Option allows you to set the "From" email address for each collector. The problem is I need to be able to have correspondence letters for the ABC customers from john.doe@abc.com and the others from john.doe@def.com. Has anyone figured out a way to accomplish this?