I asked the same question time ago. I solved it in a not-very-elegant way. I explain it:
First, I'll did it using mandrake with kde. I don't know RedHat, but I hope is not too different; if you don't use kde... I have no idea.
There are two files: one is a binary ending with .kss, located in /usr/bin.
The other is a '.desktop'-ending file, which must reside in
if they are not in that places, look for .kss files, and then look for the location of files called the same, but ending in .desktop with the 'find' command, and remove them
(for instance 'kmatrix.kss' and 'KMatrix.desktop' are a couple of such files)
I hope it helps