Thank you, David, for shedding light on this. If nothing else, I can now say "Put a sniffer on your segment, and see for yourself."
Ken -----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] Behalf Of David F. Skoll Sent: Wednesday, January 28, 2004 2:20 PM To: '[EMAIL PROTECTED]' Subject: Re: [Mimedefang] Greylist TEMPFAILS being viewed as 5.x.x PERM fails? On Wed, 28 Jan 2004, Cormack, Ken wrote: > It seems that RFC brain-dead mailers are out there, that interpret a > tempfail as if it were a 5.x.x permanent failure, and the failure is being > handed back to the sending user's MUA. No, what's going on is that the brain-dead senders receive 4xx for all their RCPT commands. They then issue a DATA command (in spite of the fact that they MUST not issue DATA unless at least one RCPT succeeded) and Sendmail correctly responds with a 5xx code. I believe Novell Groupwise has this bug. Old SLMail servers did too. > A. "fought the good fight to prove you are not sending a 5.x.x series status > code"... and won Yes. > B. Found something in your milter code or sendmail.cf that IS in fact, > sending a 5.x.x when a triplet is greylisted See above. > C. had experience with any such brain-dead MTAs that misinterperet a 4.x.x > code Yes. > D. Found a fix, short of whitelisting the problematic hosts Yes. With CanIt/CanIt-PRO, we can optionally delay greylisting until the end of the DATA phase. This wastes bandwidth, but does give most of the benefits of greylisting without triggering problems on buggy servers. Regards, David. _______________________________________________ Visit http://www.mimedefang.org and http://www.canit.ca MIMEDefang mailing list [EMAIL PROTECTED] http://lists.roaringpenguin.com/mailman/listinfo/mimedefang _______________________________________________ Visit http://www.mimedefang.org and http://www.canit.ca MIMEDefang mailing list [EMAIL PROTECTED] http://lists.roaringpenguin.com/mailman/listinfo/mimedefang
