This was a known issue for a very small number of 2.4.21-preX kernels. The nForce IDE driver is now ("now" being a couple of -preX kernels after it was first released) integrated into the AMD Viper IDE module (since it's the same chipset, or very similar, or something). In other words, if you use 2.4.21-rc6 (or thereabouts), you won't have this problem.
And of course, if you don't use the nForce IDE driver, it doesn't matter what it's called. So your solution works too.