glibc usually goes together with the gcc compiler version used and frequently a kernel that was compiled with that pair of version matched things.
Right now, you DO need source, but also need to talk on that channel and find out what makefile mods you can do. With Mandrake there is now a tool called mrproper that happily takes source and tries to reconcile it to current gcc and glibc. This little thing is one reason I like Mandrake. OTHER than that Mandrake has RPMS that work for a lot of ATI cards.
I am not knocking your choice, I also use RedHat.
Also check out this little virtual place:
http://speakeasy.rpmfind.net/
or
http://rpmfind.net/
Note there are typically 2 links for each entry-- one side leads to an RPM info page, the other leads to a direct download link.
You might also check out
http://www.pclinuxonline.com/ and ask TexStar if he knows if his ATI RPMs for Mandrake 9.0 or 9.1 have been tested on RedHat 8 or 9-- in the forums.
John Danielson.