I'm using exim4-daemon-light (debian) for manage home mail without problems.
I'm deploying a web system (php+pgsql) and I'would like to integrate user
information between the web application and exim through postgresql. Looking
at debian cache, I saw that is possible to use pgsql for lookups using
exim4-daemon-heavy.
The documentation I had read (The Exim Specification - Version 4.4x) is hard
to understand for me becouse I haven't enough knowledge about exim. Is there
any other document about this feature? Could you please help me to configure
exim4 for sql lookups?