Hmmm... Mine is in /usr/lib/xorg/modules/drivers. I wonder, the ModulePath options are supposed to be comma separated. I'm getting the felling that I didn't format it right. Should I have left out the spaces? No wait, man xorg.conf says the strings ignore whitespace... Adjust the ModulePath line ( add /usr/lib/xorg/modules/drivers), or symlink to the file?
I would add /usr/lib/xorg/modules/drivers to ModulePath and see what happens.
Michael