[CentOS] CentOS 3.4 to CentOS 4

I have upgraded to CentOS 4 from 3.4.  I am having trouble figuring out
the mail changes.  Under 3.4, Imap and POP were modules that xinetd
controlled.  Under 4.0, I have a choice of either Cyrus-Imapd or
Dovecot.  After googling all week, I was about to get my user account
authenticated under Cyrus and the saslpasswd program, as well as
dovecot.  My problem is that they don't know where my mail is.  I run
postfix, and have mail delivered to /var/spool/mail/%u.  I put this into
Cyrus' mail directory but it still doesn't see anything.  Dovecot always
tries to chdir to the user's home directory, ignoring anything I put
into dovecot.conf concerning mail locations.

Any ideas?  Thanks.