You also need to set up startup procedures, so dovecot starts up when the machine boots. (/etc/rc.d/rc5.d graphics mode, /etc/rc.d/rc3.d text mode).
Which is done using the ntsysv or chkconfig programs. This is normally done for you when you install the RPM, but some packages don't enable the service to start on boot, so you use these programs to enable them. They're the equivalent of the Windows Services applet.
