[exim] Callouts, NULL DSN

Well, I've got a problem with an SMTP server refusing a null DSN. Apparently this guy John Levine (iecc.com) refuses any connects with a MAIL FROM: <> and thus callout verification fails.

We've sent a number of mails back and forth, and it boils down to me arguing "RFC XXX, RFC XXX, RFC XXX says you MUST accept this. Sendmail, the largest producer of SMTP software in the world says you must accept this"

Then he point off to his own failed attempt at an RFC (BATV , draft-levine-mass-batv-01.txt ) and says that says it is okay, and what we are doing it wrong.

Any insights?

Steve