OK, I played around a bit with it. Here is what I found out.
Whenever you install the kernel source during your first installation, it will work just fine. When you install the kernel source afterwards via yast or manually, it won't work work without a little editing. Which files you would have to edit, I am not quite sure as of now.
Another bet would be to install the regular kernel, install nvidia drivers and then reinstall the athlon kernel.