Screen redraw problems


When changing the name of a file on the desktop the OS doesn't redraw correctly and leaves a funny white area where text used to be? - john.
If you open a finder window in list mode and you can't see the whole content of the window.
if you push alt(option) while the mouse is in the content part of the window but not over an icon or a text you have a hand that allows you to move the content to see the parts hidden.
Then you'll notice that it isn't redrawn correctly.