How do I disable dragging between items in Silverlight treeview?

Using the Silverlight treeview with the TreeViewDragDropTarget in the SL Toolkit enables me to drag & drop both into nodes as well as in between nodes.

However, in my implementation, I only want dropping onto nodes ... not in between. Is there a way to disable this or at least to trap this?

Right now, when I handle the drop event, I use the following to get my drop target:

var target = ((System.Wi开发者_开发问答ndows.FrameworkElement)(e.OriginalSource)).DataContext as Unit;

However, when I drop between two items, I don't see anything that indicates the drop was in between items. I also want to disable the line that shows up in between items ... I don't want to give the user the impression that they have the ability.

Thanks for your help.

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I wound up using Telerik's RadTreeView which provided a bit more control. Also, I wound up having some drag/drop issues using TreeViewDragDropTarget ... and from their discussion threads, it seems others were having the same issue.