[Exim] Virtual Domains - Possible Solution

As I am a relative 'newbie' to the UNIX world, I apologize if this topic has
already been covered and/or solved, but since I had a good deal of frustration
solving it myself, I wanted to share my solution in case anyone else has the
same situation.

I wanted a MTA/MDA solution that did not require system users for each mail
user, required that usernames be unique only within a given domain, kept all
the files related to a given domain in one place, supported IMAP and POP3 and
didn't cost any money.

After weeks of frustration, I ended using the config example from the exim
samples site and hacking the UW-IMAPD/IPOPD to authenticate against virtual
passwd files and user virtual domain directories.

I've got it setup so that you can have tom@??? and tom@??? be
different users. Also, all the passwords/aliases for domain1.com are in one
set of files and all the passwords/aliases for domain2.com are in another.

All the mailbox file INBOXs and/or IMAP folders for any given domain are
located in user directories under domain directories.

The ONLY down sides are that users that are not in the 'default' domain need
to login as username@??? or username%domainname.com and I haven't
figured out how to get procmail to support this configuration correctly.

I've also got a PERL script that can run from a shell or from a web page to
allow domain mail administrators access to adding/removing mail users without
sysadmin intervention.

Sample configuration:

Domain : acme.com

Password File : /etc/vmail/passwd.acme.com
Alias File : /etc/vmail/aliases.acme.com

User1 Inbox : /var/vmail/acme.com/user1/INBOX
User1 IMAP Folders : /var/vmail/acme.com/user1/folder...
User1 IMAP .folderlist : /var/vmail/acme.com/user1/.folderlist

User2 Inbox : /var/vmail/acme.com/user2/INBOX
User2 IMAP Folders : /var/vmail/acme.com/user2/folder...
User2 IMAP .folderlist : /var/vmail/acme.com/user2/.folderlist

etc

This configuration works for both POP and IMAP users since UW-IMAP provides
both.

If anyone is interested in getting this hack and admin scripts, please e-mail
me at : billyt@???. I would be happy to setup a quick web page to
show how I did it if it would help anyone out.

I am working on changing the routine to authenticate against an LDAP server,
but I have no idea when I'll get that done.

- Bill Thousand
Clarity Technology Group