in the given example if one mouses over the arrow (use instance) only the mouseover event is triggered but not the mouseout event. Opera and Mozilla render this example correctly.
Thank you for having a look at this problem.
Bug fixed in my hdd. The use shadow tree was always regenerated, even if you just altered the transform attribute -> before the mouseout event was send, the tree was already regenerated so the actual dispatch didn't take any effect. This was a tricky bug, glad you found it!
*** This bug has been marked as a duplicate of 12936 ***