diff --git a/ChangeLog b/ChangeLog
index 83db49234..06427e7a9 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,8 @@
 2015-09-11  Peter Stephenson  <p.w.stephenson@ntlworld.com>
 
+	* unposted: Config/version.mk: Update internal build to
+	5.1.1-dev-0
+
 	* unposted: Config/version.mk: 5.1.1
 
 	*  Sebastian Gniazdowski: 36489: Src/Modules/curses.c: fix bug
diff --git a/Config/version.mk b/Config/version.mk
index 21577997b..7ec276df2 100644
--- a/Config/version.mk
+++ b/Config/version.mk
@@ -27,5 +27,5 @@
 # This must also serve as a shell script, so do not add spaces around the
 # `=' signs.
 
-VERSION=5.1.1
+VERSION=5.1.1-dev-0
 VERSION_DATE='September 11, 2015'