The best I've managed is to add an "obj.parentNode.style.overflowY = 'scroll';" which gets a right hand vertical scroll bar in FF4, but the headers are no longer static an scroll with the table body. I tried "tBody.style.overflow='scroll';" and "tBody.style.overflowY='scroll';" but neither worked on the table body.
Any ideas? I'm really stuck on this and have a number of sites I use this in to display long lists of products. Without the vertical scroll in FF4 it becomes close to useless