The ipop2d, ipop3d, and imapd daemons should be invoked by your
/etc/inetd.conf file with lines such as:

pop2    stream  tcp     nowait  root    /usr/local/libexec/ipop2d   ipop2d
pop3    stream  tcp     nowait  root    /usr/local/libexec/ipop3d   ipop3d
imap4   stream  tcp     nowait  root    /usr/local/libexec/imapd    imapd

If PAM authentication support has been compiled in you will need to add
something like the following lines to /etc/pam.conf (PAM authentication is
default):

imap	auth	required	pam_unix.so
imap	account	required	pam_unix.so			try_first_pass
imap	session	required	pam_deny.so
pop3	auth	required	pam_unix.so
pop3	account	required	pam_unix.so			try_first_pass
pop3	session	required	pam_deny.so

The pam_unix module does not have session support, so we do not use it for
session management. Be sure to read up on pam.conf(5).