diff -r 8ee6c5b98d73 -r 3ff969da57ef hgext/obsolete.py
--- a/hgext/obsolete.py	Tue May 29 11:15:19 2012 +0200
+++ b/hgext/obsolete.py	Tue Jun 05 20:43:39 2012 +0200
@@ -705,7 +705,7 @@
                 del self._unstableset
             if '_suspendedset' in vars(self):
                 del self._suspendedset
-            if '_extinct' in vars(self):
+            if '_extinctset' in vars(self):
                 del self._extinctset
 
         def addobsolete(self, sub, obj):