I have some kind of animation problem(like the one with window minimizing). When I press the application launcher button on taskbar, then the animation is not black, it's green like a graphical defect. I have the same problem with every gnome based desktop distribution(FC3, FC4-test3, Ubuntu 5.04). It's interesting because I have no problems with the minimizing animation and Show Desktop and other buttons- only with application buttons(firefox, mail, tatum player etc).

Nvidia Geforce FX 5200(without any drivers yet)
Samsung SyncMaster 753DFX