diff --git a/DEVELOPING b/DEVELOPING
index ff391e4..ea6945a 100644
--- a/DEVELOPING
+++ b/DEVELOPING
@@ -44,7 +44,8 @@
 
     1.  If you change any of the code generation scripts in
     tools/munger/scripts you must re-run make -C tools/munger to
-    regenerate the OpenFlow message classes.
+    regenerate the OpenFlow message classes. Make sure you
+    commit the generated code.
 
 Adding Your Own Test Cases
 ++++++++++++++++++++++++++