AlphaRegistration Добавить поле в виде выпадающего списка из 3х эллементов обьединенных в одно значе - Joomla 1.5: Общие вопросы

<?$maybe_birth = date(Y)-8;?>
<form action="test.php" method="POST">
<select name="year" id="year">
<option value="" selected="selected">Год</option>
<? 
for ($c_year=1960;$c_year<$maybe_birth;$c_year++)
	{echo '<option value="'.$c_year.'">'.$c_year.'</option>';} ?>
</select>
<select name="mounth" id="mounth">
	<option value="" selected="selected">Месяц</option>
	<? for ($c_mounth=1;$c_mounth<13;$c_mounth++)
	{if ($c_mounth<10) {$c_mounth= '0'.$c_mounth;} 
	echo '<option value="'.$c_mounth.'">'.$c_mounth.'</option>';} ?>	
</select><select name="day" id="day">
		<option value="" selected="selected">День</option>
		<? for ($c_day=1;$c_day<32;$c_day++)
		
	{if ($c_day<10) {$c_day= '0'.$c_day;} 
	echo '<option value="'.$c_day.'">'.$c_day.'</option>';} ?>	
</select>
<input type="submit" value="Отправить" />
<? $form_year = $_POST['year']; $form_mounth = $_POST['mounth']; $form_day = $_POST['day'];

$birth_date_array= array($form_year,$form_mounth,$form_day);

$birth_date = implode("-", $birth_date_array);

if (!empty($form_year)) {echo $birth_date;} else {};
?>

<input type="hidden" name="displaybirthdateAUP" id="displaybirthdateAUP" value="<? echo $birth_date; ?>" />