Scribble Example

[Mario Kemper <mario kemper googlemail com>]

I am playing around with muppet's scribble example and it's working like
a charm but if i move the mouse cursor very fast there are only single
rectangles drawn. 
It seems to me that the needed events (motion_notify) are not passed
fast enough. Is there any way to prevent this or a workaround? 

Greetings
Mario