Your kernel is probably unable to load the modules needed to locate your volumes.
My best guess is your initrd is not in the right place. It needs to be in the same directory as the installed kernel.
Also, it's not a good idea to follow Debian instructions for a RedHat system. In general it's ok, but you are doing something that is relatively distribution specific.
James Roth
2010-07-08 02:30:01