Funny thing is, despite the first mail server repeatedly failing it still
managed to send every devliver attempt to the recipient (based on the user's
feedback that she received multiple copies).  It also looks like it gave
Imail the impression that it didn't deliver the mail, so my mail server kept
trying.  Are those assumptions correct?
Let's take a look.

But, before that, I'll just say that mercantile.net's DNS isn't set up too well in my opinion, with 11 NS records. It's MX record is 8 bytes shorter than the maximum length for UDP (504 bytes versus the 512 byte maximum). Legal, but immediately places them as a suspect.

20030129 222613 127.0.0.1 SMTP (1376) Connect mercantile.net [151.196.161.4:25] (1)
This is good -- IMail is sending to the correct IP, the primary MX record.

20030129 222634 127.0.0.1 SMTP (1376) 220 **********************************************2*0*********
They have a broken firewall -- strike 2 on their part.

20030129 222634 127.0.0.1 SMTP (1376) >EHLO ggchamber.org
20030129 222634 127.0.0.1 SMTP (1376) 500 Unknown or unimplemented command
Most likely another sign of the broken firewall; strike 3 on their part. This is legal, but undesirable.

20030129 222634 127.0.0.1       SMTP (1376) >DATA
20030129 222634 127.0.0.1       SMTP (1376) 354 Ready for data
20030129 222634 127.0.0.1       SMTP (1376) >.
20030129 223034 127.0.0.1       SMTP (1376) rl-recv: Blocking call cancelled
20030129 223034 127.0.0.1       SMTP (1376)
20030129 223034 127.0.0.1       SMTP (1376) SMTP_DELIV_FAILED
20030129 223034 127.0.0.1       SMTP (1376) >QUIT
This most likely means that they broke the TCP/IP connection partway through the E-mail. In any case, they did not send an "OK, Message received" type response, so I'd say they are definitely at fault. Most likely their broken firewall is badly broken, not just broken.

My guess is that their broken firewall probably see you send the "." (the "I'm done sending this message" command), and disconnects the session, being terribly afraid that you will try hacking their mailserver after sending an E-mail. However, by doing this before the response is sent back from their mailserver, they are going to get inundated with copies of your E-mail (as it is impossible to know that they did accept the E-mail).

20030129 225605 127.0.0.1       SMTP (2780) >.
20030129 225605 127.0.0.1       SMTP (2780) 250 2.6.0
<[EMAIL PROTECTED]> Queued mail for delivery
Here, the E-mail was delivered properly to their backup mailserver, and IMail should have stopped trying to deliver the E-mail at this point.

-Scott
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