Creating a repo for users of RHEL is a great solution that allows for YUM usage on RHEL, however it doesn't solve the exact problem with the package of YUM on RHEL.
The issue is the package itself. EPEL has no way of shipping a 100% working version of YUM on RHEL 4. So, I still say we place something in yum.conf to let the RHEL user know that YUM won't "just work" until they help it out some.
stahnma