[wx.lib.ogl] bug when repainting LineShapes on scrolled screen

[Joki]

Hi all,

I'm using the ogl library and found a bug that occurs when the libraries
LineShapes are repainted on a scrolled window, for example due to moving an
attached shape.

The bug is, that the LineShapes are painted on the very top of the screen,
also on the task bar of the system. The painting is not restricted to the
Canvas area.

The bug can be viewed in the wxDemo OGL example (Misc. Section). Just scroll
the window down to hide some LineShapes that connect the other Shapes. Then
drag a random Shape and the invisible LineShapes are painted.

I'm using 

    + Python 2.5.1-5ubuntu5.1
    + wxPython 2.8.4.0-0ubuntu3 (GTK and demo)

Maybe someone has the same problem and could give me a hint on how to
solve this problem.

Regards,

Joki