Heeeelp! Jquery Sortable

Heeeelp! Jquery Sortable

Hi Folks,
I´ve created a jquery sortable exactly as this one:
http://interface.eyecon.ro/demos/sort.html

But, when I drop the box it slides very fast to the new position (exactly as in the example above). I want the box to slide smoothly when dropped, just like happens here, at bbc site ( http://bbc.co.uk ).

How can I do this?
I've read a lot of documentation and forums and can't find a solution. I tried use "revert" parameter but it doesn't work or I'm using it the wrong way.

Thanks in advance,
Regis