var expDays = 30;
var exp = new Date(); 
exp.setTime(exp.getTime() + (expDays*24*60*60*1000));

function DeleteCookie (name) {  
	var exp = new Date();  
	exp.setTime (exp.getTime() - 1);  
	var cval = GetCookie (name);  
	document.cookie = name + "=" + cval + "; expires=" + exp.toGMTString();
}

function SetCookie (name, value) {  
	var argv = SetCookie.arguments;  
	var argc = SetCookie.arguments.length;  
	var expires = (argc > 2) ? argv[2] : null;  
	document.cookie = name + "=" + escape (value) +
	((expires == null) ? "" : ("; expires=" + expires.toGMTString())) + ("; path=/");
}

function GetCookie (name) {  
	var arg = name + "=";  
	var alen = arg.length;  
	var clen = document.cookie.length;  
	var i = 0;  
	while (i < clen) {    
	var j = i + alen;    
	if (document.cookie.substring(i, j) == arg)      
		return getCookieVal (j);    
		i = document.cookie.indexOf(" ", i) + 1;    
		if (i == 0) break;   
	}  
	return null;
}

function getCookieVal(offset) {
	var endstr = document.cookie.indexOf (";", offset);
	if (endstr == -1)
		endstr = document.cookie.length;
		return unescape(document.cookie.substring(offset, endstr));
}