It turns out that exim on the mail server that tmda runs on was not putting a Return-Path: header onto incoming mails. The server has recently been switched from postfix to exim, so presumably the reason that I haven't had this problem before was that postfix did do this.
AIUI from what I've read in RFC 822 and elsewhere, Return-Path: should be added by the MTA at final delivery, and should contain the same as $SENDER does at that time. With that in mind, I've simply added
:0fw | formail -z -c -a "Return-Path: $SENDER"
to .procmailrc before the message is passed to tmda, and things now work.
Things are now working for me, but the question still in my mind out of curiosity is: is it exim or tmda that is broken here?
Does passing the message to procmail (and then to tmda) count as "final delivery", or is that only when it is actually put into a mailbox somewhere? If the latter, then exim is correct not to append this header and TMDA should do this itself before delivery. I suspect that "final delivery" is a technical term in the world of email, so I'll leave it to knowledgable people to enlighten me as to what exactly it means :-)
THanks for all the help and suggestions when I was grappeling with this - they set me on the right track to solving it.
-Simon.
-- "Standby Pyro...Pyro..Go...No...No wait!" --------------------------------------------------------------- Simon Waldman, UK email: [EMAIL PROTECTED] --------------------------------------------------------------- _____________________________________________ tmda-users mailing list ([email protected]) http://tmda.net/lists/listinfo/tmda-users
