SpamCop's MX is giving double errors on unknown addresses

[DavidT]

Please start by reading this topic:

http://forum.spamcop.net/forums/index.php?showtopic=9116

The issue that arose in that topic, is that when an SMTP connection comes into the MX for SpamCop.net email accounts, and asks to deliver to a bad address, SpamCop's server is currently producing an unusual (IMO) "double error" like this:

550 sorry, no such user here (#5.7.1)

553 sorry, that domain isn't allowed to be relayed thru this MTA (#5.7.1)

A delivery attempt on a bad address should only produce the "no such user" error, and not the "domain isn't allowed to be relayed" error, which has an altogether different purpose.

This seems to be a bug and so I'll send it to TPTB (i.e. JT).

DT

[DavidT]

Three days later and not a peep.

DT

[jefft]

Three days later and not a peep.

DT

Yes, I got your message. Anything after the first error code should be ignored. It's a bug, but one that doesn't hurt anything. We'll look into fixing this, though.

JT

[DavidT]

Anything after the first error code should be ignored. It's a bug, but one that doesn't hurt anything.

The key word there is "should." However, over in this other thread:

http://forum.spamcop.net/forums/index.php?showtopic=9116

you'll see that the buggy SMTP responses (I've *never* seen double responses like that, and I've been doing "live" Port 25 connections to servers all around the world for well over 10 years) seem to have caused grief for another SC email customer with his mailing list subscriptions. That may very well have been due to an incorrect interpretation by the delivering MTA, but it did indeed "hurt" something.

DT