>Does any MTA other than Postfix implement nullmx? I did some experiments. My qmail system rejects on nullmx immediately for roughly the same reason postfix does, a general rejection on bad MX records.
Among web mail, Yahoo rejects immediately, Gmail and AOL don't reject immediately and I don't know yet what will eventually happen, and Hotmail/Outlook.com sometimes gives an odd error message and sometimes sends it, again dunno what will eventually happen. So it's not universally implemented, but there's a significant part of the mail world that does it. R's, John
