/**
     * Generates a 'checkbox' element.
     *
     * @access public
     *
     * @param string|array $name If a string, the element name.  If an
     * array, all other parameters are ignored, and the array elements
     * are extracted in place of added parameters.
     * @param mixed $value The element value.
     * @param array $attribs Attributes for the element tag.
     * @param mixed $options 
     * @return string The element XHTML.
     */
    public function formCheckbox($name, $value = null, $attribs = null)

The options parameter was removed in revision 7972, but it's still in the comment and in the docs http://framework.zend.com/manual/en/…