Help with Draggables

HI -

I'm trying to set up a test page that has 3 columns. Within each column is a draggable div. I'd like the user to be able to drag any of the divs contained within the left right or center divs.

I can't get it working - I've looked over the wiki docs and elsewhere but the only examples I've seen deal with unordered lists.

Here is my code: