Index: export_docbook.module
===================================================================
--- export_docbook.module	(revision 318)
+++ export_docbook.module	(working copy)
@@ -254,7 +254,7 @@
   $xhtml = export_docbook_tidy($html);
   $docbook = export_docbook_convert($xhtml);
 
-  $title = "<title>" . $node->title . "</title>\n";
+  $title = "<title>" . check_plain($node->title) . "</title>\n";
   if ($depth == 1) {
     $root_element = 'book';
     $output .= "<book id=\"node-" . $node->nid . "\" lang=\"$locale\">\n";