diff --git a/CHANGES.txt b/CHANGES.txt
index 03862dd..3dae57b 100644
--- a/CHANGES.txt
+++ b/CHANGES.txt
@@ -1,6 +1,12 @@
 CHANGES
 =======
 
+0.4.1 (unreleased)
+------------------
+
+- ...
+
+
 0.4.0 (2013-11-24)
 ------------------
 
diff --git a/setup.py b/setup.py
index 68f46f0..72eb51c 100644
--- a/setup.py
+++ b/setup.py
@@ -23,7 +23,7 @@ def read(*rnames):
 
 setup(
     name='keas.build',
-    version='0.4.0',
+    version='0.4.1dev',
     author = "Stephan Richter and the Zope Community",
     author_email = "zope-dev@zope.org",
     description='A Build System',