RE: [Exim] mail system without unix users

>Look at the courier packages, there is pop, imap, smtp and such. It can
>work with mysql, without system users and stores messages in maildir
>format. I use this on a server with a few thousand mailboxes and I'm
>satisfied. (I use exim as MTA, though, not courier's own smtpd)

Thats what i am starting off to do. Can you recommend any reading to
integrate it all?