The information at http://www.ubuntu.com/testing/natty/beta#Graphics%20and%20display makes me think that this is actually a duplicate of bug 711378 rather than bug 642877. Examining the other duplicates of bug 711378 seems to confirm this. So I'll go ahead and mark this as a duplicate of bug 711378 instead.
The information at http:// www.ubuntu. com/testing/ natty/beta# Graphics% 20and%20display makes me think that this is actually a duplicate of bug 711378 rather than bug 642877. Examining the other duplicates of bug 711378 seems to confirm this. So I'll go ahead and mark this as a duplicate of bug 711378 instead.