Here is how I managed to build rpms for and install courier on Fedora Core 7 (on Sep 3rd 2007).

Adjust the version numbers to the latest current version if you wish.

# yum -y install libtool  openldap-devel postgresql-devel   gdbm-devel  pam-devel libtool-ltdl-devel redhat-rpm-config /usr/include/fam.h openssl-perl pcre-devel

# wget http://unc.dl.sourceforge.net/courier/courier-0.56.0.tar.bz2
# wget http://unc.dl.sourceforge.net/courier/courier-authlib-0.59.3.tar.bz2

# mkdir $HOME/rpm $HOME/rpm/SOURCES $HOME/rpm/SPECS $HOME/rpm/BUILD \
$HOME/rpm/SRPMS $HOME/rpm/RPMS $HOME/rpm/RPMS/i386

# echo "%_topdir    $HOME/rpm" >> $HOME/.rpmmacros

# rpmbuild -ta courier-authlib-0.5*.tar.bz2
# su
# rpm -Uvh rpm/RPMS/i386/courier-authlib-0.5*-1.i386.rpm
# rpm -Uvh rpm/RPMS/i386/courier-authlib-userdb-0.5*-1.i386.rpm
# rpm -Uvh rpm/RPMS/i386/courier-authlib-devel-0.5*-1.i386.rpm
# exit

# mv courier-0.5*.0.tar.bz2 rpm/SOURCES/
# tar -xvjf rpm/SOURCES/courier-0.5*.0.tar.bz2 *courier.spec
# perl -pi -e "s#_unpackaged_files_terminate_build 1#_unpackaged_files_terminate_build 0#" courier-0.5*.0/courier.spec
# mv courier-0.5*.0/courier.spec rpm/SPECS
# rmdir courier-0.5*.0

# rpmbuild -bb --without fax --without ldap rpm/SPECS/courier.spec

# cd $HOME/rpm/RPMS/i386
# su
# rpm -Uvh courier-0*.rpm courier-imapd-0*.rpm courier-pop3d-0*.rpm
# exit

Based on  VHCS installation instructions for CentOS

Cheers,

Motin