function initWScroll()
{
	_p = document.getElementById("ad_skyscraper");
	var container = document.getElementById("main");
	var container_height = container.offsetHeight;
	var padding = 0;
	if (document.documentElement.clientHeight)
	{
		var browser = document.documentElement.clientHeight;
	}
	else
	{
		var browser = window.innerHeight;
	}

	var padding_top = browser - padding;
	
	if(_p)
		{
		
			var _offset = getCurrentYPos();
			var _top = _offset + padding;
			_p.style.marginTop = _top + "px";
		}

	window.onscroll = function()
	{
		if(_p)
		{
			var _offset = getCurrentYPos();
			var _top = _offset + padding;
			_p.style.marginTop = _top + "px";
		}
	}		
}

function getCurrentYPos()
{
	var _offset = 0;
    if (document.body && document.body.scrollTop)
      _offset =  document.body.scrollTop;
    if (document.documentElement && document.documentElement.scrollTop)
      _offset = document.documentElement.scrollTop;
    if (window.pageYOffset)
      _offset =  window.pageYOffset;
      
    return _offset;
 }

if (window.addEventListener){
	window.addEventListener("load", initWScroll, false);
	window.addEventListener("resize", initWScroll, false);
}
else if (window.attachEvent){
	window.attachEvent("onload", initWScroll);
	window.attachEvent("onresize", initWScroll);
}