Jon,
There are valid and useful scenarios that require the bounces address to
differ from both RFC2822 From and RFC2822 Sender.
JK> Have you got a list of some such scenarios? Seriously, that would help. Or
JK> some reference that you can point me to.
Legitimate bulk-mail sending (for example, newsletters) is the current,
major example.
In fact, redirecting bounces to special servers is a key functionality
for serious mail-sending services.
In your MUA, you will probably find a Return-Path header. This contains
the address that was in the RFC2821 Mail From field. It is frequently
(usually?) different from both RFC2822 From and RFC2822 Sender.
d/
--
Dave Crocker <dcrocker-at-brandenburg-dot-com>
Brandenburg InternetWorking <www.brandenburg.com>
Sunnyvale, CA USA <tel:+1.408.246.8253>