diff -r e59b5e5918a5 -r 2990ce46fc2d mercurial/transaction.py
--- a/mercurial/transaction.py	Thu Aug 07 11:56:32 2014 -0700
+++ b/mercurial/transaction.py	Thu Aug 07 10:54:17 2014 -0700
@@ -154,7 +154,7 @@
 
         if file in self.map or file in self.backupmap:
             return
-        backupfile = "%s.%s" % (self.journal, file)
+        backupfile = "%s.backup.%s" % (self.journal, file)
         if self.opener.exists(file):
             filepath = self.opener.join(file)
             backuppath = self.opener.join(backupfile)