python-imaging is available in RHEL-5.0, so the epel-5 version is not required. Could you follow at least the first 2 steps of: http://fedoraproject.org/wiki/PackageMaintainers/PackageEndOfLife in the python-imaging EL-5 branch? Once the dead.package is there it will be more clear that this package isn't used anymore.
python-imaging is available in EPEL because it is not available in the RHEL5-server channel.