function getCookie(name){ 
var cname = name + "="; 
var dc = document.cookie; 
if(dc.length > 0) { 
	begin = dc.indexOf(cname); 
	if (begin != -1) { 
		begin += cname.length; 
		end = dc.indexOf(";", begin); 
		if (end == -1) 
			end = dc.length; 
		return unescape(dc.substring(begin,end));
	 }
} 
return null; 
} 
function isLoggedOn(){ 
var username=getCookie("username"); 
return (null!=username); 
}