Philip Hazel wrote: >
> Notice what happens: the first test is correctly rejected at the RCPT TO
> stage. Exim then sends RSET and MAIL FROM:<> again. This time, the
> remote host gives the response that Exim logs! So as far as I can
> see, the remote host is behaving weirdly. (And the remote host is not
> Exim.)
Looks like some kind of overly aggressive anti-dictionary-attack
measure. You should probably have a chat with the postmaster.