--- a/mercurial/context.py	Tue Dec 11 20:13:21 2012 +0100
+++ b/mercurial/context.py	Wed Jan 16 05:21:11 2013 +0100
@@ -67,7 +67,7 @@
             self._rev = r
             self._node = repo.changelog.node(r)
             return
-        except (ValueError, OverflowError):
+        except (ValueError, OverflowError, IndexError):
             pass
 
         if len(changeid) == 40: