public function convertUnserialized(Array $serialized, ContentStream $contentStream = NULL) {
    if (isset($contentStream)) {
      foreach ($serialized as $serializedEntry) {
        $entry = $this->unserializeEntry((object) $serializedEntry);
        $entry->setContentStream($contentStream);
      }
      return $contentStream;
    } else {
      $unserialized = array();
      foreach ($serialized as $serializedEntry) {
        $unserialized[] = $this->unserializeEntry($serializedEntry);
      }
    }
    
    return $unserialized;
  }