Passing variables to a viewScript Decorator
===

I have tried adding a partial to my form using the Zend Form's viewScript decorator, however i seem unable to pass along variables to the partial. Here's my code:

In the controller i add the form:    	

    $form = new Content_Form_ContentForm(array("categories" => $sortedCategories));
    $form->submit_button->setLabel("Add content");
    $this->view->form = $form;

Then inside the form i add the viewscript:

    public function setCategories($categories) {
    	$this->setDecorators(array(array('ViewScript', array(
    			'viewScript' => 'partials/dtreePartial.phtml',
    			'List'=>"{$categories}",
    	))));
    }
I have tried printing the options for the view script by using `print_r($this->getDecorator('ViewScript')->getOptions());` wich results in `Array ( [viewScript] => partials/dtreePartial.phtml [List] => Array )`
However when i run it all, the script returns an error about the List not existing.

I have the feeling i am missing something but i am unsure as to what it is. Any advice or solutions will be appreciated! :)