--- a/hgfastobs.py	Sat Nov 16 20:43:44 2013 -0500
+++ b/hgfastobs.py	Sat Nov 16 20:44:37 2013 -0500
@@ -105,6 +105,7 @@
         transmit.extend(obsolete.precursormarkers(urepo[node]))
     for node in boxedges:
         transmit.extend(obsolete.successormarkers(urepo[node]))
+    transmit = list(set(transmit))
     xmit, total = len(transmit), len(repo.obsstore._all)
     repo.ui.status(
         'boxpush: about to transmit %d obsolete markers (%d markers total)\n'