W B Hacker <wbh@???> writes:
> 'All of the above' - and a great deal more - have been built-in to
> Exim for (some variable number) of years, so no identifiable need.
I agree that Exim's ACL mechanisms have proven to be quite powerful
for enforcing policies at the SMTP level -- and probably more flexible
than the other players.
However, with each step of "innovation" in the arms race about
delivering and preventing spam and malware, countermeasures have led
to accelerated growth in size and complexity of MTA software itself.
Sendmail's main incentive for including the Milter interface may have
been the unmaintainablity of their own configuration file format, but
I believe that they have done a Good Thing by providing a rather
simple API for extending and customizing the MTA. A short look at
<
http://www.milter.org/> shows that this API has proven quite useful
for both experimental antispam features and site-local customizations.
I believe that tight integration of the Milter interface into the ACL
system will make Exim even more powerful. You may think of it as a
generalization of the content-scanning API.
Do not fear: There are no plans to turn Exim into Sendmail that I am
aware of. ;-)
Cheers,
-Hilko