function wheel(event)
{
	var delta = 0;
	
	if (!event) event = window.event;
	
	if (event.wheelDelta)
	{
		delta = event.wheelDelta/60; //120;
		//if (window.opera) delta = -delta;
	}
	else if (event.detail)
	{
		delta = -event.detail/3;
	}
	
	if (delta)
	{
		var area = getViewportRect();
		//alert(document.body.clientHeight);
		window.scroll(area.x-delta*50, area.y);
		
		if (event.preventDefault) event.preventDefault();
		event.returnValue = false;
	}
}

if (window.addEventListener) window.addEventListener('DOMMouseScroll', wheel, false);
window.onmousewheel = document.onmousewheel = wheel;

function getViewportRect()
{
	var scrl = getScroll();
	
	return {
		x: scrl.x,
		y: scrl.y,
		width: YAHOO.util.Dom.getViewportWidth(),
		height: YAHOO.util.Dom.getViewportHeight()
	}
}

function getScroll()
{
	return {
		x: document.body.scrollLeft || document.documentElement.scrollLeft,
		y: document.body.scrollTop  || document.documentElement.scrollTop
	}
}