Apple has released a software graphics update for certain iBook models.
The update, "iBook G4 Graphics Update 1.0" is intended for the 12-inch 1GHz and 14-inch 1.2GHz iBook G4s.
Apple says the patch "updates the graphics driver to fix a compatibility issue that may exist with applications that use OpenGL."
Apple adds that the 12MB download will "replace the old ATIDriver.bundle with a new one."
The update requires Mac OS X 10.3.3 and is available here.