The imap rpm that comes with RH5.9 does not include the pam
config file for the ipop3d. This causes ipop3d to just sit,
hang and eventually disconnect when a user tries to connect
to the server. The imap rpm is severely lacking
documentation so it took a strace to determine the problem.
The fix is to copy /etc/pam.d/imap to /etc/pam.d/pop .
This has been fixed.