diff --git a/src/Control/Monad/Base.hs b/src/Control/Monad/Base.hs
--- a/src/Control/Monad/Base.hs
+++ b/src/Control/Monad/Base.hs
@@ -5,6 +5,11 @@
 {-# LANGUAGE FlexibleInstances #-}
 {-# LANGUAGE UndecidableInstances #-}
 
+#if MIN_VERSION_transformers(0,4,0)
+-- Hide warnings for the deprecated ErrorT transformer:
+{-# OPTIONS_GHC -fno-warn-warnings-deprecations #-}
+#endif
+
 module Control.Monad.Base (
     MonadBase(..),
     liftBaseDefault
@@ -27,6 +32,10 @@
 import Control.Monad.Trans.Error
 import Control.Monad.Trans.Cont
 
+#if MIN_VERSION_transformers(0,4,0)
+import Control.Monad.Trans.Except
+#endif
+
 #if !MIN_VERSION_base(4,4,0) && HS_TRANSFORMERS_BASE__ORPHANS
 import Control.Monad (ap)
 #endif
@@ -92,6 +101,9 @@
 TRANS(L.StateT s)
 TRANS(S.StateT s)
 TRANS(ContT r)
+#if MIN_VERSION_transformers(0,4,0)
+TRANS(ExceptT e)
+#endif
 #undef TRANS
 
 #define TRANS_CTX(CTX, T) \
diff --git a/transformers-base.cabal b/transformers-base.cabal
--- a/transformers-base.cabal
+++ b/transformers-base.cabal
@@ -1,5 +1,5 @@
 Name: transformers-base
-Version: 0.4.1
+Version: 0.4.2
 Category: Control
 Stability: experimental
 Synopsis: Lift computations from the bottom of a transformer stack