[typo] drag drop admin doesn't work

[Jeroen Houben]

Hi,

I just installed typo. I can remove items from the sidebar but dragging 
stuff onto the right doesn't work. The progress indicator keeps 
spinning, but nothing happens and this error is thrown in javascript:

Sortable.options(oldParentNode) has no properties
// this function Sortable.options(oldParentNode).onChange(element);

This happens on osx firefox 2.0.4, camino and safari

Any ideas?

Jeroen