function check_email(val) {
	    rx = /^[0-9a-z]([-.]?[_0-9a-z]){0,63}@[0-9a-z]([-.]?[0-9a-z]){1,184}\.[a-z]{2,4}$/i;
      //  rx = /^[0-9a-z]([-.]?[_0-9a-z])*@[0-9a-z]([-.]?[0-9a-z])*\.[a-z]{2,4}$/i;
        if (val == '' || !rx.test(val)) {
            alert('Emailadres is niet correct ingevuld.');
            return false;
        } else return true;
}