diff --git a/Annex/Journal.hs b/Annex/Journal.hs
index 9f4d295996..e68591ce2c 100755
--- a/Annex/Journal.hs
+++ b/Annex/Journal.hs
@@ -68,8 +68,8 @@ journalFile file repo = gitAnnexJournalDir repo </> concatMap mangle file
   where
 	mangle c
 		| c == pathSeparator = "_"
-		| c == '_' = '__'
-		| otherwise = c
+		| c == '_' = "__"
+		| otherwise = [c]
 
 {- Converts a journal file (relative to the journal dir) back to the
  - filename on the branch. -}