diff --git a/docs/lcdproc-dev/lcdproc-dev.docbook b/docs/lcdproc-dev/lcdproc-dev.docbook
index d20a1d7..13e2227 100644
--- a/docs/lcdproc-dev/lcdproc-dev.docbook
+++ b/docs/lcdproc-dev/lcdproc-dev.docbook
@@ -1,6 +1,6 @@
 <?xml version='1.0'?>
-<!DOCTYPE book PUBLIC "-//OASIS//DTD DocBook XML V4.1//EN"
-                      "http://www.oasis-open.org/docbook/xml/4.1/docbookx.dtd" [
+<!DOCTYPE book PUBLIC "-//OASIS//DTD DocBook XML V4.1.2//EN"
+                      "http://www.oasis-open.org/docbook/xml/4.1.2/docbookx.dtd" [
   <!ENTITY bookinfo SYSTEM "bookinfo.docbook">
   <!ENTITY introduction SYSTEM "introduction.docbook">
   <!ENTITY shared-files SYSTEM "shared-files.docbook">