Sorry for the late replyt guys. I have been very busy the last few weeks.
Please not that couriers userdb is very sensitive and that it works with tab's and not spaces. Thanks to all the guys that help out with the tread to help other guys get this sorted. I'n my inviroment i make sure that emails is the same as usernames when added to ispconfig.
I am also busy working on a gui frontend for my isp system. All users, ftp , email , dns and apache virtual hosts are read from mysql.
No users get's add to /etc/passwd , everyting is mysql backend driven.
Software used is as folows: smtp : exim
spam: dspam (user has own spam corpus to train so no mail spesified as spam wil ever rich user again)
apache: no virtual hosts entry's per domain. ( uses mod_rewrite) so only directory's needs to be created.
All loging of traffic get written to mysql for easy accounting.
Will let you guys know as soon as finished with it. +- 1 month.