httpwebwitch - 2:58 am on Jan 8, 2011 (gmt 0)

that almost worked,
but the file /etc/pki/rpm-gpg/RPM-GPG-KEY-EPEL did not exist...

I found a reference to that file, here:

https://fedoraproject.org/keys

which links to this :
https://fedoraproject.org/static/217521F6.txt

So, I created a file /etc/pki/rpm-gpg/RPM-GPG-KEY-EPEL and pasted that key into it.

EGADS, it WORKED

I did have to remove the version of rrdtool that was installed by EPEL and replace it with a different one:
# yum remove rrdtool
# yum install rrdtool-1.2.27-3.el5.x86_64

once that was in, the rest was a breeze...
# yum install ganglia ganglia-gmetad ganglia-gmond ganglia-web

THANK YOU lammert!
I owe you one!