I have the same problem on OpenSolaris 2009.06 when I use Adobe Acrobat and open up a very large PDF document. The scroll bar that I use to scroll up and down in the Adobe Acrobat document gets corrupted. It sometimes happens in Firefox as well, but doesn't seem to happen to Evince Document Viewer.
The best way to duplicate the bug is to open up a 300+ page e-book in the official version of Acrobat reader that Adobe made for OpenSolaris in OpenSolaris 2009.06 snv_111b -- This message posted from opensolaris.org
