diff --git a/src/Hakyll/Core/UnixFilter.hs b/src/Hakyll/Core/UnixFilter.hs
index e6d4610..34b2ecb 100644
--- a/src/Hakyll/Core/UnixFilter.hs
+++ b/src/Hakyll/Core/UnixFilter.hs
@@ -129,7 +129,9 @@ unixFilterIO writer reader programName args input = do
 
     -- Read from stderr
     _ <- forkIO $ do
+        hSetEncoding errh localeEncoding
         err <- hGetContents errh
+        _   <- deepseq err (return err)
         hClose errh
         writeIORef errRef err
         putMVar lock ()