Have you guys tried the stock kernel rather than using Mandrake kernel source? When there are issues like that go to the stock kernel and determine if the problem lies in your distros kernel source. The driver has no problems with 2.4.22 on Fedora, the issue is what compiler is used, and configuration (perhaps hardware conflicts). But its not incompatibility with the kernel source (in this specific issue.. perhaps with Mandrake it IS)
"..the triumph of evil is for good men to do nothing."
VIDIA video driver RPMs for Fedora
:: see yum repo at livna.org