Как сделать мобильный ( обратный) редирект?

if( isset( $_REQUEST['action'] ) and $_REQUEST['action'] == "mobiledisable" ) $_SESSION['mobile_disable'] = 1;
if( isset( $_REQUEST['action'] ) and $_REQUEST['action'] == "mobile" ) { $_SESSION['mobile_enable'] = 1; $_SESSION['mobile_disable'] = 0;} //Эта строчка может отсутствовать в старых версия DLE

if ( $config['allow_smartphone'] AND !$_SESSION['mobile_disable'] ) {

if ( check_smartphone() ) {

if ( @is_dir ( ROOT_DIR . '/templates/smartphone' ) ) {

$config['skin'] = "smartphone";
$smartphone_detected = true;
$config['allow_comments_wysiwyg'] = "no";

}

}

}

$msite = clean_url ( 'm.site.ru' ); //m.site.ru меняем на свой поддомен, на котором будет находится смарт версия.

if ( isset( $_REQUEST['action'] ) and $_REQUEST['action'] == 'mobiledisable' )
{
$_SESSION['mobile_disable'] = true;
header( 'HTTP/1.1 303 See Other' );
header( 'Location: ' . $config['http_home_url'] );

die();
}

if ( $config['allow_smartphone'] )
{
if ( clean_url ( $_SERVER['HTTP_HOST'] ) != $msite AND ( ( ! $_SESSION['mobile_disable'] AND check_smartphone() ) OR ( isset( $_REQUEST['action'] ) and $_REQUEST['action'] == 'mobile' ) ) )
{
$_SESSION['mobile_disable'] = false;
header( 'HTTP/1.1 303 See Other' );
header( 'Location: http://' . $msite . '/' );

die();
}

if ( clean_url ( $_SERVER['HTTP_HOST'] ) == $msite AND @is_dir ( ROOT_DIR . '/templates/smartphone' ) )
{
$config['skin'] = "smartphone";
$smartphone_detected = true;
$config['ajax'] = false;
$config['allow_comments_wysiwyg'] = "no";

}
}

<a id="go2full" class="ico" href="/index.php?action=mobiledisable">Полная версия сайта</a>