Dragged div change places with destination

Dragged div change places with destination

Hi.

Maybe a bit complex to explain. I have a grid with 9 images 100 x 100 px like this (each number symbolize a picture):

1 2 3
4 5 6
7 8 9

What I want is that the user can drag and drop e.g. 9 over 1 and they change places like this:

9 2 3
4 5 6
7 8 1

Sortables from jquery UI will not work since their solution is using floats. That will "push" all the boxes to the right or left e.g.:

9 1 2
3 4 5
6 7 8

thanks in advance.