I have a small app that allows a user to share an item by generating an email to a supplied email address. We set the "from" and "reply to" values to be the sender's address, so that when the email reaches the recipient, it appears to have come from the sender.

This works wonderfully except when an email gets bounced. Currently, on bounces, exim attempts to redeliver the message periodically while simultaneously sending error emails back to the sender. I'd rather have those emails basically routed to an empty mailbox somewhere as there's nothing really that the sender can do about it.

I found some documentation on bounced emails here:

http://www.exim.org/exim-html-4.67/doc/html/spec_html/ch46.html

and it claims that "Exim sends a message to the original sender, or to an alternative configured address.", but it doesn't say exactly how to configure an alternative address.

Ideas?