Dragging an object outside of a overflow:hidden

If you'll take a look at this: http://jsfiddle.net/hunterscott/JYLVQ/ You'll notice that if you try to drag the image, you can see the helper move, but it won't leave the gallery box. I have a feeling this is a CSS thing, but I'm not sure where it is.

Edit: Sorry, I need to be more specific, since that fiddle is pretty watered down from the full project. Gallery-wrap has to be set to overflow:hidden because it is an image carousel that shows 5 images at a time, and the rest are hidden. The user clicks arrows to advance through 开发者_运维百科them. If I make gallery-wrap visible, then the images that shouldn't be seen are seen stacked below the first 5.

#gallery-wrap

is the culprit, it has overflow:hidden; set.

EDIT: ah, thanks for the clarification. Does this help?