diff --git a/data-ref.cabal b/data-ref.cabal
--- a/data-ref.cabal
+++ b/data-ref.cabal
@@ -1,5 +1,5 @@
 Name:             data-ref
-Version:          0.0.0.1
+Version:          0.0.1
 License:          BSD3
 License-File:     LICENSE
 Author:           Henning Thielemann <haskell@henning-thielemann.de>
@@ -27,11 +27,11 @@
 Source-Repository this
   type:     darcs
   location: http://hub.darcs.net/thielema/data-ref/
-  tag:      0.0.0.1
+  tag:      0.0.1
 
 Library
   Build-Depends:
-    transformers >=0.2 && <0.5,
+    transformers >=0.4 && <0.5,
     stm >=2.2 && <2.5,
     base >=2 && <5
 
diff --git a/src/Data/Ref.hs b/src/Data/Ref.hs
--- a/src/Data/Ref.hs
+++ b/src/Data/Ref.hs
@@ -22,6 +22,7 @@
 import qualified Control.Monad.Trans.Writer.Strict as MWS
 import qualified Control.Monad.Trans.Cont as MC
 import qualified Control.Monad.Trans.Error as ME
+import qualified Control.Monad.Trans.Except as MEx
 import qualified Control.Monad.Trans.Maybe as MM
 import qualified Control.Monad.Trans.Reader as MR
 import qualified Control.Monad.Trans.Identity as MI
@@ -73,6 +74,7 @@
 
 instance C m => C (MM.MaybeT m) where new = newLifted
 instance (ME.Error e, C m) => C (ME.ErrorT e m) where new = newLifted
+instance (C m) => C (MEx.ExceptT e m) where new = newLifted
 
 instance C m => C (MC.ContT r m) where new = newLifted
 instance C m => C (MR.ReaderT r m) where new = newLifted