diff --git a/doc/de/index.docbook b/doc/de/index.docbook
index e34e9f3..1192e87 100644
--- a/doc/de/index.docbook
+++ b/doc/de/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 kdiff3 "<application
 >KDiff3</application
 >">
diff --git a/doc/et/index.docbook b/doc/et/index.docbook
index b06c99e..4cbf36b 100644
--- a/doc/et/index.docbook
+++ b/doc/et/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 kdiff3 "<application
 >KDiff3</application
 >">
diff --git a/doc/fr/index.docbook b/doc/fr/index.docbook
index 86bd294..5752637 100644
--- a/doc/fr/index.docbook
+++ b/doc/fr/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 kdiff3 "<application
 >KDiff3</application
 >">
diff --git a/doc/it/index.docbook b/doc/it/index.docbook
index 11d4b21..dcb0004 100644
--- a/doc/it/index.docbook
+++ b/doc/it/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 kdiff3 "<application
 >KDiff3</application
 >">
diff --git a/doc/nl/index.docbook b/doc/nl/index.docbook
index 8f3a294..d3ec93e 100644
--- a/doc/nl/index.docbook
+++ b/doc/nl/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 kdiff3 "<application
 >KDiff3</application
 >">