diff --git a/doc/index.docbook b/doc/index.docbook
index d2a7f070..50c1874b 100755
--- a/doc/index.docbook
+++ b/doc/index.docbook
@@ -1,5 +1,5 @@
 <?xml version="1.0" ?>
-<!DOCTYPE book PUBLIC "-//KDE//DTD DocBook XML V4.1.2-Based Variant V1.1//EN" "dtd/kdex.dtd" [
+<!DOCTYPE book PUBLIC "-//KDE//DTD DocBook XML V4.2-Based Variant V1.1//EN" "dtd/kdex.dtd" [
   <!ENTITY kappname "<application>krfb</application>">
   <!ENTITY package "kdenetwork">
   <!ENTITY % addindex "IGNORE">