Sven Geggus wrote:
[...]
> I check for valid domains, but I am not able to check for valid local parts?
> Granted, that it would be best to not even accept spam like this, but how
> would I do this? As I already said, I don't think that checking for
> originating IP-numbers like gmy would be a good idea.
Have a look at "smtp-callback", which tries to send mail to the
envelope-sender. It would do "mail from: <>; rcpt to: sender" at one of
the yahoo-mail-servers and could be used to block non-existing
yahoo-senders.
However, it causes additional traffic both for you and for yahoo.
Personally, I don't care and added an smtp-callback to SpamAssassin as
an additional score. Well, I should add a cache soon.
Sometimes I receive questions of other postmasters wondering about
log-entries like "remote host closed connection unexpectedly", but of
course those domains can be excluded by a callback.
I'm not sure wheter smtp-callback was intended to be used on such a
level, though. ;-)
--
CU,
Patrick.