未找到类别 - 在Kohana 3.1上制作助手

got a fresh install of Kohana 3.1. Trying to make my own helpers. I have created a helper in the application/classes/helpers/ directory. I have called the file javascript.php, the class is called Helper_Javascript and has a static function that just returns "alert('sometext')" here it isgot a fresh install of Kohana 3.1. Trying to ma