the problem I was haveing is that the /lib/modules/2.4.20-28.9/build/include/linux/modversions.h file was NOT present in my build tree.
Yes I was getting the exact same error.
When I deinstalled the 28.9 kernel and the kernel-source rpms then reinstalled them as stated in my previous post the modversions.h file was present. I don't know why it was not there the first time and I don't know why it was there the second time but it was there and the Nvidia installer ran with now problem.
Ipsa scientia potestas est
32 bit graphical interface for a
16 bit patch to an
8 bit operating system internally coded for a
4 bit processor written by a
2 bit company that can't stand
1 bit of competition