[ Thanks to Andrew
Weber for this link. ]
“Dovecot version 2 has been available for some time but it may
not be in the repositories for CentOS for a long time to come. This
tutorial will show you how to perform a basic install of Dovecot
version 2 and get it working for one domain… other tutorials will
follow with additional configurations.“The repository for CentOS 5.5 does not have the version
required for postgresql-libs. As a result you will need to enable
the testing repository for CentOS. Warning: Any time you install
from the testing repository you will be taking on additional risk,
so think twice about using it on a production machine. Create
access to the CentOS testing repo. Add the Centos-Test.repo in
/etc/yum.repos.d.”