qmail-pop3d and users groups

[Roberto Samarone Araujo \(RSA\)]

    Hi,

            I have a qmail server running in a FreeBSD 4.2 and using
qmail-pop3d. I would like to know if I could set up qmail-pop3d to work only
for users in some groups in /etc/group file. Is it possible to do this? How
?

                            thanks,

                        Roberto Samarone Araujo