Hope somebody out there is more familiar with the black arts of ESMTP than I am.

Here the deal. I have two mail servers running Qmail. One is a pretty vanilla version. The other trying to do everything under the sun.

Although both accept and send mail just fine one of them has major problems with Comcast. Their server just dumps the mail going to them or bounces mail sent from them to me. It's... strange.

So I've been digging and it looks like it has something to do with the auth method but I'm not sure why. Can anyone shed some light on this?

Here's two telnet sessions.

The one that works:
220 thisoneworks.com ESMTP
ehlo
250-thisoneworks.com
250-PIPELINING
250 8BITMIME
quit

The one that doesn't:
ESMTPdoesntwork.net
ehlo
250-doesntwork.net
250-AUTH LOGIN CRAM-MD5 PLAIN
250-AUTH=LOGIN CRAM-MD5 PLAIN
250-PIPELINING
250-STARTTLS
250 8BITMIME

Anyone want to take a shot?

Thanks,
Iggy

Just answering my own question here (he he)

So there are a few places you can set your domain in control files for qmail

Me
Plusdomain
Defaulhost

I had gone ahead and set my domain in all three. For some reason this screwed up the esmtp greeting so that instead of something like this:

220 thisoneworks.com ESMTP

It spewed out something like this:

ESMTPdoesntwork.net

Appearantly some mail servers don't really care and gloss over it and other mail servers (Comcast comes to mind) care quite a bit. To the point that they'll just abandon the handshake. Hard to diagnose, at least for me.

The solution was to remove my domain name from all of the above files except ME.

Viola. Comcast now delivers the mail and Qmail "should" be magically delicious to every other mail server on the net.

Hope that helps some other schmuck out there setting up qmail. :D

Iggy