public function rules()
	{
		return array(
			'title' => array(
				array('not_empty'),
			),
			'content' => array(
				array('not_empty'),
			),
			'image' => array(
				array('Upload::not_empty'),
				array('Upload::valid'),
				array('Upload::image'),
				array('Upload::size' => array(':value', '4M')),
				array('Upload::type' => array(':value', array('jpg', 'png', 'gif'))),
			)
		);
	}