function default_homepage(obj, url)
{
	obj.style.behavior='url(#default#homepage)'; 
	obj.setHomePage(url);
}
function addFavorite(url, title)
{ 
	try
	{
		window.external.AddFavorite(url, title);
	}
	catch(e)
	{
		alert('当前浏览器不支持此功能');
	}
}