Let's chalk this one up to the Monday Morning Blues.
I'm running through a CentOS 6.x test server and needed to install the EPEL repos. For some reason I managed to install the RHEL5 rpm instead of the RHEL6. (D'Oh!)
This is a quick fix on removing the repo completely to install the proper one.
0. Got root? (or sudo)
1. Remove Repo
rpm -qa | grep epel
Expected output (in my case)
yum remove epel-release-5-4
yum clean all