On Mon, 23 Dec 2002, Alan J. Flavell wrote:
> >From even my limited experience, there seem to be nontrivial numbers
> of mailers which react to 5xx responses at various stages either by
> proceeding as if nothing had gone wrong, or by treating the 5xx as a
> temporary failure (e.g many of the hosts that we reject because they
> presented illegal character(s) in the HELO string).
>
> So far, it seems that the best chance for getting rid of bad mail
> detected in earlier phases is to postpone the 5xx response until the
> RCPT TO phase.
Exactly. That is why Exim 4 started out without any ACLs that ran
earlier than RCPT. I have added them recently because people made enough
fuss...
--
Philip Hazel University of Cambridge Computing Service,
ph10@??? Cambridge, England. Phone: +44 1223 334714.
