PHP Fatal error: Call to undefined function taxonomy_nodeapi()

PHP Fatal error: Call to undefined function taxonomy_nodeapi() in luceneapi_node.module on line 475

When using Lucene API search module and core taxonomy module is not activated I receive this error when trying to search content.

Part of code:

  // fetch comments, taxonomy terms for snippet
  if ($add_comments) {
    $node->body .= comment_nodeapi($node, 'update index');
  }
  $node->body .= taxonomy_nodeapi($node, 'update index');

For the comment module this is done in luceneapi_node.module on line 452.
This should also be done for the taxonomy module.