Due to the increasing number of mis-configured servers out
there (mostly Exchange), I've had to drop the syntax check
on HELO and EHLO - we were simply missing out on too much
mail.
But I would still like to send out mails to the postmasters
of domains that are served by these servers, telling them
what needs to be fixed.
My suggestion is to have some option that can be enabled,
which makes Exim log invalid HELO/EHLOs with a warning to
mainlog (or perhaps some other log file), but without an
error being sent to the "offending" server. I don't know if
anyone else sees the need for this, but I think it would be
neat :)
