Sortable: position off when container scrolled horizontally

See the fiddle: http://jsfiddle.net/shhQuiet/t2vnfmh4/4/embedded/result/

Resize the fiddle screen until you see a horizontal scrollbar. Scroll all the way to the right and then trying dragging the elements. Their horizontal position is still retained from the initial position.

I have tried to mitigate the issue with no luck by adding this:

$('#scroller').scroll(function() {
    $('.items').sortable("refreshPositions");
});