--On Sunday, July 17, 2011 10:37:53 PM -0400 Stephen Harris <lists at spuddy.org> wrote: > RFC2821 says: > - The domain name given in the EHLO command MUST BE either a primary > host name (a domain name that resolves to an A RR) or, if the host > has no name, an address literal as described in section 4.1.1.1. > > So, pretty much, HELO or EHLO greeting _must_ match to an IP. > > (RFC821 actually wanted the HELO to match the connecting host, but > 2821 just says it must be an A record or an address literal). Thank you for posting that. Despite the garden path we got down, my previous comments didn't say that you had to accept *anything*, but merely that too stringent of a check would eliminate some valid mailers. There's nothing like stirring a can of worms :) Devin