hopefully you've already downloaded and installed the appropriate rpm from here:
ftp://download.nvidia.com/XFree86/Linux-x86
If that didn't, or you've compiled a custom kernel, you may need to try to install the below kernel module package:
ftp://download.nvidia.com/XFree86/Li....0-4363.tar.gz
I use custom kernels all of the time and the .tar.gz file is the only way to go ..