public function add_metadata_manifest(cc_i_metadata_manifest $met) {
        $metanode = $this->node("//imscc:manifest[@identifier='".
                                $this->activemanifest->manifestID().
                                "']/imscc:metadata");
        $nmeta = $this->activemanifest->create_metadata_node($met, $this->doc, $metanode);
        $metanode->appendChild($nmeta);
    }