function readCookie(name) {
	var cks = document.cookie.split(';');
	for (var i=0; i < cks.length; i++) {
		var c = cks[i];
		while (c.charAt(0)==' ') c = c.substring(1,c.length);
		if (c.indexOf(name+"=")==0) return c.substring(name.length+1,c.length);
	}
	return null;
}