diff -r a8aba2921456 -r 578fcc22b469 mercurial/cmdutil.py
--- a/mercurial/cmdutil.py	Thu Oct 18 22:12:15 2012 +0200
+++ b/mercurial/cmdutil.py	Thu Oct 18 17:54:34 2012 +0200
@@ -1744,7 +1744,7 @@
                 new = repo[newid]
                 obs = [(old, (new,))]
                 if node:
-                    obs.append((ctx, (new,)))
+                    obs.append((ctx, ()))
 
                 obsolete.createmarkers(repo, obs)
             tr.close()