diff -r bf840a3d1af2 -r be9c4131a8f4 mercurial/hg.py
--- a/mercurial/hg.py	Thu Sep 02 11:20:23 2010 +0200
+++ b/mercurial/hg.py	Thu Sep 02 12:08:13 2010 +0200
@@ -311,7 +311,8 @@
             # we need to re-init the repo after manually copying the data
             # into it
             dest_repo = repository(ui, dest)
-            src_repo.hook('outgoing', source='clone', node='0'*40)
+            src_repo.hook('outgoing', source='clone',
+                          node=node.hex(node.nullid))
         else:
             try:
                 dest_repo = repository(ui, dest, create=True)