Problem with jQuery UI droppables

Problem with jQuery UI droppables

Test page: http://www.simpsoncrazy.com/content/games/jigsaw.html

If you drag an image in Opera, it jumps to the bottom of the screen (or off screen). I have a feeling this is a result of my coding in some way because the jQuery UI demo pages don't exhibit this problem.

Any ideas why this is happening?

EDIT: I fixed that problem by updating to the latest versions of jQuery and jQuery UI.