I've noticed that a page with an active modal window will scroll vertically forever in IE6.
I finally tracked it down to this line: if(ie6&&$('html,body').css({height:'100%',width:'100%'})&&o){o=o.css ({position:'absolute'})[0];for(var y in {Top:1,Left:1}) o.style.setExpression(y.toLowerCase(),"(_= (document.documentElement.scroll"+y+" || document.body.scroll"+y+")) +'px'");} I would assume that the overlay keeps getting moved down the page making the page height longer and longer as you scroll. I toyed around with removing that line and just setting the overlay to be positioned absolutely at 0,0 and sized at the document's height. But I've found that select boxes then flicker through the modal as you scroll. The expression is the most effective thing I've seen to prevent that bleed-through on scroll. So now I'm back to square 1. Has anyone else solved for this problem?