actually it's not quite mrpropper that fixes this thing (because i got this problem again with 4496 and a new kernel)
look for smp_call_function on this page to find another user with this issue
I upgraded to kernel 2.4.20-20.7 and had the problem again, i was only able to resolve this by compiling my sound driver NOT in a module and compiling the Intel/Sis/AMD sound driver AS a module. I had not fixed the problem by using mrproperr before i fixed it because i rearanged the kernel compile options to get it to stop the unresolved symbols. So this is definitly an NVIDIA problem with custom compiled kernels that require you to have funky modules already built before using the nvidia kernel. So, The problem is the nvidia module should auto include symbols that the custom compile is forced to include.