Mail Server without password entry

[Shashi Dahal]

     What steps must I take in order to set up a qmail mail server
(smpt and pop3) that resides on a Linux box that doesn't contain all of
the users in the local passwd file?  I believe I can authenticate the
POP
users remotely via RADIUS and checkpasswd, but will the same be true for

the smtp connections and deliveries?
        I apoligize if this seems like a novice question.

Thanks in advance.

Shashi