I just checked the latest quantal proposed kernel 3.5.0-31, and it works. And the latest released kernel 3.5.0-29.49 works as well. But 3.5.0-30 doesn't work. So, I think the kernel team has fixed the problem which introduced from 3.5.0-30.
I just checked the latest quantal proposed kernel 3.5.0-31, and it works.
And the latest released kernel 3.5.0-29.49 works as well.
But 3.5.0-30 doesn't work.
So, I think the kernel team has fixed the problem which introduced from 3.5.0-30.