This compiler check is a safety measure nividia built in to be sure their module is compiled with exactly the same CC version which was used to compile your kernel. Maybe it is just pedantic, and telling the nvidia that is can use gcc 4.0 as HappyTux suggests is ok.
Just FYI, when I run into the same problem, I installed the compiler version as asked for by nividia and compiled and installed the module without any problem.
If I remember well, I installed gcc using this command line:
Code:
apt-get install gcc=3.3.5-3
(Change the version number for the correct one as asked for by nividia. Use
Code:
apt-cache search showpkg gcc
to see the exact notation for the version name you want to install.
jlinkels