It should be noted that exim4 on debian supports the one large conf
file. If you put any valid exim configuration file in
/etc/exim4/exim4.conf debian exim will use it as its configuration file.
Also, at first install, exim-daemon-light/heavy will ask you if you want
the multi config file format or the one large config format.
The large config format the only way I ever used to configure exim on
debian systems, and this way should be supported by exim mailing list as
it's the same as the "regular" way of doing config (except for config
file place and name).
Also for people who tell exim3 is still shipped by debian, it will only
be shipped by debian if you upgrade from an old debian which used exim3
to a new one. So it's probably better to tell them to *fully* upgrade
their installation by running "apt-get install exim4-daemon-heavy".
There is a debian script which will try to convert old exim3 configs to
new exim4 configs when you do the upgrade (better try before prod :)).
The exim4 package is far less messed up by debian than the apache2 package.