draggable_element Messing up CSS for IE7

I am having trouble with draggable_element and come IE7 css. I have a list where I want the items in the list to be draggable. I need the list to have a fixed height so I would like a scrollbar. I use overflow:auto and everything works great in Firefox and Safari. But IE doesn't respect the overflow:hidden. Well, it kind of does. It creates the scroll bars but lets everything spill out past it.

After some testing I tracked it down to calling draggable_element on the list items. If I remove that then everything displays correctly.

You can see an example here:

http://gregdevore.screenstepslive.com/lessons/850

Any help would be greatly appreciated.