diff -r 8b874f8cd29f -r efc579fdaf69 mercurial/revlog.py
--- a/mercurial/revlog.py	Thu Oct 02 16:22:02 2008 +0200
+++ b/mercurial/revlog.py	Sat Oct 04 10:14:39 2008 +0200
@@ -852,7 +852,7 @@
                 node = bin(id)
                 r = self.rev(node)
                 return node
-            except TypeError:
+            except (TypeError, LookupError):
                 pass
 
     def _partialmatch(self, id):