--- a/mercurial/exchange.py	Tue Apr 01 23:41:32 2014 -0700
+++ b/mercurial/exchange.py	Fri Apr 04 16:41:51 2014 -0700
@@ -596,7 +596,7 @@
     """
     # build bundle here.
     cg = changegroup.getbundle(repo, source, heads=heads,
-                               common=common, bundlecaps=None)
+                               common=common, bundlecaps=bundlecaps)
     if bundlecaps is None or 'HG20' not in bundlecaps:
         return cg
     # very crude first implementation,