I always ran the release of Safari simultaneously with running Webkit's nightly build, running different sites on each browser and I never had a problem till recently. After upgrading to OS 10.6.4, I cannot launch Webkit without almost immediately a graphical redraw problem starting. Windows overdraw each other and aren't erased when they are closed and the Mac cannot be used at all. I have to restart the computer. I've upgraded to three or four builds of Webkit, including yesterday's build, and the problem has persisted. As soon as I launch Webkit now, the draw problem begins. I haven't tested to determine the exact conflict: whether it is with Safari or something else I'm running.