function validateEmail() { 
  var email = document.getElementById('email');
  email = email.value;
  if (window.RegExp) {
    var reg1str = "(@.*@)|(\\.\\.)|(@\\.)|(\\.@)|(^\\.)";
    var reg2str = "^.+\\@(\\[?)[a-zA-Z0-9\\-\\.]+\\.([a-zA-Z]{2,3}|[0-9]{1,3})(\\]?)$";
    var reg1 = new RegExp(reg1str);
    var reg2 = new RegExp(reg2str);
    if (!reg1.test(email) && reg2.test(email)) {
      document.mailing_list_form.submit();
	  return true;
    }
    return alert('not valid email address !!');
  } else {
    if(str.indexOf("@") >= 0){
      document.mailing_list_form.submit();
	  return true;
	}
    return alert('not valid email address !!');
  }
}