A quick comment on MAIL FROM: My wife just got bitten by a major ISP
that's apprently implemented rDNS checks against MAIL FROM. She was
sending from her notebook at home, using a domain name she owns, through
an outbound-only MTA on our home network.
OK, I'm a complete idiot.
Mark, I totally misread your message. Even though you put MAIL FROM in
great big capitals I read HELO.
My excuse, not enough coffee, plus I'm literally in the middle of a
conversation with the chap who does postmaster for our "corporate" mail
system. He is laughing "fit to bust a gut".
D'oh.