Thanks for the answer. I'm currently using 10.04 with Linux kernel 3.0.0.12, which is backported from Oneiric (from Ubuntu kernel team's PPA). So I'm sure that what causes the bug isn't the difference between kernel versions.
I'm booting Lucid with "nomodeset" option, because it runs too slow when I don't use that option. However, on Oneiric, that option causes lack of support for Unity 3D. Without using it, Compiz doesn't start, so both Unity's and GNOME's 3D versions cannot be started although it seems that Unity 3D support is available.
I think the best solution for this problem is returning to LTS for now. I hope the bug will be solved soon.
@André Oliva,
Thanks for the answer. I'm currently using 10.04 with Linux kernel 3.0.0.12, which is backported from Oneiric (from Ubuntu kernel team's PPA). So I'm sure that what causes the bug isn't the difference between kernel versions.
I'm booting Lucid with "nomodeset" option, because it runs too slow when I don't use that option. However, on Oneiric, that option causes lack of support for Unity 3D. Without using it, Compiz doesn't start, so both Unity's and GNOME's 3D versions cannot be started although it seems that Unity 3D support is available.
I think the best solution for this problem is returning to LTS for now. I hope the bug will be solved soon.