function checkMail(email)
{
	var x = email;
	var filter  = /^([a-zA-Z0-9_\.\-])+\@(([a-zA-Z0-9\-])+\.)+([a-zA-Z0-9]{2,4})+$/;
	return (filter.test(x));
}

function checkEmpty(value) {
  return (value.length != 0); 
}