window.addEvent('domready', function() {
    var dropdowns = $ES('select.nav_auto_direct');
    dropdowns.each(function (item, index) {
        item.addEvent('change', function (e) {
            var url = item.getProperty('value');
            // must be a valid url
            var re1 = /^\//g;
            var re2 = /^http[s]?:\/\//g;
            if (url.match(re1) || url.match(re2)) {
                top.location.href = url;
            }
        });
    });

});