Dragging item onto scroll bar drops item at the bottom

[GoogleCodeExporter]

What steps will reproduce the problem?
1. Create a list box with IsDragSource="True" and IsDropTarget="True"
2. Drag and drop a list box item onto the scroll bar

What is the expected output? What do you see instead?
Expected: Drop fails or the cursor changes to show that dropping is not enabled 
on the scroll bar, no changes to the list.
Reality: Item moved to the bottom of the list.
It looks like the default drop target is the last item in the list. So when the 
algorithm cannot determine which item is the target, it just drops at the end 
of the list.

What version of the product are you using? On what operating system?
0.1.2 on Windows XP

Please provide any additional information below.
I am binding the items to the list box

Original issue reported on code.google.com by harms.bl...@gmail.com on 8 Jul 2010 at 1:16