QTreeWidget and QUndoStack?

Hej,

I have subclassed a QTreeWidget for showing a structure to the user.
The user is also able to drag items in that tree around (only Qt::MoveAction). Works fine.

Now, I also have a QUndoStack to give the option to undo things.

Question is now: How can I offer undo for the move actions in the QTreeWidget?!?!

Thanks,
Oli