--- a/book1/preface.xml	Thu Jan 26 16:51:38 2006 -0500
+++ b/book1/preface.xml	Fri Feb 03 16:27:35 2006 -0500
@@ -1,6 +1,11 @@
 <?xml version='1.0'?>
 <!DOCTYPE preface PUBLIC "-//OASIS//DTD DocBook XML V4.2//EN"
-          "/usr/share/sgml/docbook/dtd/xml/4.2/docbookx.dtd">
+          "/usr/share/sgml/docbook/dtd/xml/4.2/docbookx.dtd"
+[
+    <!ENTITY % xinclude SYSTEM "../xinclude.dtd" >
+    <!ENTITY % local.section.class "|xi:include">
+    %xinclude;
+]>
 <preface id="base_intro" lang="fr"
   xmlns:xi="http://www.w3.org/2001/XInclude">
   <title>Introduction</title>