Droppable tolerance

Droppable tolerance

Hi,
I have a collapsable/expandable tree menu for folders on my server. I
was trying to make a file draggable and droppable on a folder.
All works well on the folders that are visible in the tree after page
load. But if I expand a part of the tree, there appears to be no
droppable area for the newly shown folders. They have a link and all,
and they have been set up as a droppable, but no event is triggered
when I drag a file over it.
Someone who has experienced the same? Is it solvable? Can I
dynamically 'activate' the droppable?
Regards,
Edwin
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