Index: src/Darcs/Util/Tree/Monad.hs
--- src/Darcs/Util/Tree/Monad.hs.orig
+++ src/Darcs/Util/Tree/Monad.hs
@@ -45,6 +45,7 @@ import Data.Int( Int64 )
 import Data.Maybe( isNothing, isJust )
 
 import qualified Data.ByteString.Lazy as BL
+import Control.Monad
 import Control.Monad.RWS.Strict
 import qualified Data.Map as M
 
