I recently got a complaint that my fetchmail rejected a mail, but would
not tell why. It returned a "General SMTP/ESMTP error". It turned out
(from the Postfix logs) that the body_checks (a content filter)
triggered, and after CRLF.CRLF, Postfix replied 550 improper use of
8-bit data in message header.
It looks as though transact.c would discard recipient information at
around line #1030, but that without the recipient information, the
error response would not be presented in part #2 of the 3-part bounce.
I'm currently lost in the code complexity, I don't see what the right
way to fix it. My ultimate goal is that NO reply of the SMTP listener
(that fetchmail forwards to) will EVER be hidden from a bounce as it
currently happens in handle_smtp_report when msg->recipients has been