Gnome2 Desktop showing graphic-errors

[cyberfish]

Hi there!

I emerged gnome last night and configured my x today. It's working with twm when I try "startx". GDM works fine, too.

But when I login then and the gnome desktop is loaded, I have massive graphical errors on the background and partially in dialogs. There are colored lines and boxes on the background and they change when I i.e. open an terminal-window an move the window over the desktop. My collegue told me something about "double-buffering-errors", but I don't know how to fix it. It seems as if the redrawing of the background creates errors.

When gnome is loading and finished loading, I can see the background image without errors for half a second. Then without touching anything, the background errors automatically appear.

I hope anyone can help me. Thanx in advance!

Regards,
Oliver.