var d = new Date();
var f = { format: "%x%n" };
var s = "%x:\n";
s += " Default:\t" + YAHOO.util.Date.format(d, f);
s += " en-US:\t" + YAHOO.util.Date.format(d, f, "en-US");
s += " en-GB:\t" + YAHOO.util.Date.format(d, f, "en-GB");
alert(s);