diff -r 0a8e7f81e8ae -r 0cfda08afd24 mercurial/wireproto.py
--- a/mercurial/wireproto.py	Tue May 27 17:04:48 2014 -0500
+++ b/mercurial/wireproto.py	Wed May 28 14:22:24 2014 -0700
@@ -803,7 +803,7 @@
         finally:
             fp.close()
             os.unlink(tempname)
-    except bundle2.UnknownPartError, exc:
+    except bundle2.BundleValueError, exc:
             bundler = bundle2.bundle20(repo.ui)
             bundler.newpart('B2X:ERROR:UNKNOWNPART', [('parttype', str(exc))])
             return streamres(bundler.getchunks())