function stretchBackground()
{
	if (!document.getElementById('box_wrapper'))
		return;
	//if (document.body.scrollHeight>document.body.clientHeight)
		//return;
	var f=getPosition(document.getElementById('footer'));
	var c=document.getElementById('box_wrapper');
	var cp=getPosition(c);
	document.getElementById('box_wrapper').style.minHeight=f.y-cp.y-40 + "px";
}

function getPosition(e)
{
        var left=0;
        var top=0;
        do
        {
        	left+=e.offsetLeft;
        	top+=e.offsetTop;
        } while (e=e.offsetParent)

        return {x:left, y:top};
}