After upgrading to edgy pre-release, nvidia module doesn't modprobe on -generic kernel

My system profile is here:

http://hwdb.ubuntu.com/?xml=1f04acee99d97fae095286849a50f8c0

I recently upgraded from dapper to the Edgy pre-release. This installed the "linux-generic" package, as well as "linux-restricted-modules-generic" (same for -386).

Under the -386 kernel in ubuntu, nvidia works fine. However, when booted into the -generic kernel (2.6.17-10-generic), the nvidia module will not load and Xorg fails to start, complaining about how it can't find the nvidia module. I tried modprobing nvidia, and get the following message:

error running install command for nvidia

This rather opaque message leaves me nowhere. If someone can tell me how I'm supposed to find out more information about this particular error, I will reboot to -generic again and try to find out whatever information I can.