Which POP3 server to use?

[Doug Fields <dfields-list-debian@pexicom.com>]

Hello all,

I've been trying to decide which POP3 server to use.

My requirements include:

1) Ability to use PAM for authentication, or have a simple way of extending 
the authentication to use a highly customized authentication scheme (for 
which I will write a PAM module)
2) Ability to have a special directory specified where the UNIX 
mailbox-format files reside
3) Uses standard UNIX mailbox-format files

I've looked at Courier - but that is a whole enormous system (can I use 
just the POP daemon?). Also, solid POP3, but that is only 0.15, which 
doesn't necessarily "sound" good. ipop seems not to support PAM. What about 
Cyrus POP3? That seems like an overkill IMAP solution without 2 and 3 
support above.

In the past I have used the qpopper modified for 1 and 2 above. However, I 
would like to use a more feature filled version (e.g., qpopper does not 
have UIDL support).

Your thoughts would be greatly appreciated.

Thanks,

Doug