When i try to do a translation for the ArticleHolder page from the tutorial i get this error:
Call to a member function getAllFields() on a non-object in wegebrot/sapphire/core/model/Translatable.php on line 588

My main language is english. The second one is german.

Can anybody help me?

Here is my ArticleHolder.php (also attached as a file to this post):

<?php

/**
 * Defines the ArticleHolder page type
 */
class ArticleHolder extends Page {
	static $db = array(
	);
	static $has_one = array(
	);
   
	static $allowed_children = array('ArticlePage');
	static $icon = "mysite/images/treeicons/news";
}
 
class ArticleHolder_Controller extends Page_Controller {
	function init() {
		RSSFeed::linkToFeed($this->Link() . "rss");	
		parent::init();
	}
	
	function rss() {
		$rss = new RSSFeed($this->Children(), $this->Link(), "The coolest news around");
		$rss->outputToBrowser();
	}
}

?>