function EMail(s) {
        var a = false;
        var res = false;
        if (typeof (RegExp) == 'function') {
            var b = new RegExp('abc');
            if (b.test('abc') == true) { a = true; }
        }

        if (a == true) {
            reg = new RegExp('^([a-zA-Z0-9\\-\\.\\_]+)' +
                       '(\\@)([a-zA-Z0-9\\-\\.]+)' +
                       '(\\.)([a-zA-Z]{2,4})$');
            res = (reg.test(s));
        }
        else {
            res = (s.search('@') >= 1 &&
                    s.lastIndexOf('.') > s.search('@') &&
                    s.lastIndexOf('.') >= s.length - 5)
        }
        return (res);
    }