I need to be able to display ads on email forwarded through a server (preferably postfix) based on the demographic information of the recipient. Basically a message will arrive for [email protected] and be forwarded to [email protected] with a small advertisement at the bottom.
I would like to use postfix because it appears to be able to use mysql data for various tasks, which would be beneficial so that the system could be controlled by a web app that feeds the database.
I'd prefer to use OpenX for the ad server due to targetting channels (used to select ads based on demographic information), the ability to do text ads as well as email zones, and the ability to run it locally. Other ad servers that are better suited to this problem are acceptable, of course.
The core of the problem, as I see it, is being able to write something at the bottom of any given email message. Of course html messages make this even trickier, but I'd settle for having a solution that works for plain text and work up from there.
Commercial software is an option as well, but a few days of intermittent searching hasn't turned anything up.