Sortable problem on chrome browser

Sortable problem on chrome browser

Using Sortable on a table in a chrome browser gives a weird behaviour. Dragging a row around the table makes a gap appear between the top row and the table header. dragging the lowest row outside the table makes a gap between the rows. 
i've been looking for a solution all over but none found. is there any here?

thanx,
Thomas


EDIT: further inquiring showed me that it has something to do with chrome behaviour with calculating heights of elements. anyone?