I updated backend_gtk.py in cvs to remove the DBL_BUFFER
> code - it was just an experimental feature and I do not
> think anyone had a use for it, and it was confusing the
> rest of the code. I added the call to
> self.window.clear_area() which should solve the
> problem. Could someone using PyGTK 2.6 install from cvs and
> let me know if it works.
These changes fixed the problem for 2.6.