Someone

function smarty_function_age($params, &$smarty)
{

    if (!pnSecAuthAction(0, 'advProfile::', 'Plugin::age.php', ACCESS_READ)) {
        return false;
    }

    extract($params);
    unset($params);

    if (!isset($uid) || !is_numeric($uid)) {
        return false;
    }

	//
	// Inputs
	//

	$BIRTHDAY = pnUserGetVar('_BIRTHDAY', $uid);
	$BIRTHMONTH = pnUserGetVar('_BIRTHMONTH', $uid);
	$BIRTHYEAR = pnUserGetVar('_BIRTHYEAR', $uid);


	// -----------------
	// Begin Code
	// -----------------
	
	$Now = mktime( 0, 0, 0, date("n"), date("j"), date("Y") );
	$Then = mktime( 0, 0, 0, $BIRTHMONTH, $BIRTHDAY, $BIRTHYEAR );
	
	$age = floor((((($Now - $Then) / 60) / 60) / 24) / 365.25);
	
	//
	// Output
	//
	
    @include_once('modules/advProfile/pnlang/'.pnVarPrepForOS(pnUserGetLang()).'/age.php');

    if (isset($assign)) {
        $smarty->assign($assign, $age);
    } else {
        return $age;
    }

}