diff --git a/monad-gen.cabal b/monad-gen.cabal
--- a/monad-gen.cabal
+++ b/monad-gen.cabal
@@ -1,5 +1,5 @@
 name:                monad-gen
-version:             0.3.0.0
+version:             0.3.0.1
 synopsis:            A simple monad for generating fresh integers
 description:
     This module provides a simple monad transformer @GenT@ to enumerate unique values within
diff --git a/src/Control/Monad/Gen.hs b/src/Control/Monad/Gen.hs
--- a/src/Control/Monad/Gen.hs
+++ b/src/Control/Monad/Gen.hs
@@ -24,7 +24,6 @@
 import Control.Monad.Gen.Class
 import Control.Monad.Identity
 import Control.Monad.Reader
-import Control.Monad.Reader.Class
 import Control.Monad.State
 import Control.Monad.Writer.Class
 
@@ -74,13 +73,9 @@
   liftIO = GenT . liftIO
 instance MonadCont m => MonadCont (GenT e m) where
   callCC f = GenT $ callCC (unGenT . f . (GenT .))
-
-#if MIN_VERSION_mtl(2, 2, 1)
-#else
 instance MonadError e m => MonadError e (GenT e' m) where
   throwError = GenT . throwError
   catchError m h = GenT $ catchError (unGenT m) (unGenT . h)
-#endif
 
 successor :: (e -> e) -> Successor e
 successor = Successor