[greylisting] > Nice job, Andy. But a Groupwise 5.5 sender gets bounced with this message:
>
> DATA503 valid RCPT command must precede DATA
>
> What is going on here?
Looks like this Groupwise 5.5 sender agent (is that a MUA or an
MTA?) is horribly broken.
-> MAIL FROM:<sender_address>
<- 250 Ok
-> RCPT TO:<rcpt_address>
<- 450 you are greylisted, try again later
-> DATA
<- 503 valid RCPT command must precede DATA
Which means that this Groupwise sender agent is trying to
send the message anyway even if there was no valid (=250 Ok code)
RCPT TO address before. That will cause Exim to give him a
503 permanent error for the "protocol violation".
