--- a/mercurial/obsolete.py	Tue Oct 14 13:23:52 2014 -0700
+++ b/mercurial/obsolete.py	Tue Oct 14 13:25:13 2014 -0700
@@ -83,6 +83,7 @@
 
 # Options for obsolescence
 createmarkersopt = 'createmarkers'
+allowunstableopt = 'allowunstable'
 
 ### obsolescence marker flag