diff -r -u ghc-6.0.1.orig/libraries/base/Control/Exception.hs ghc-6.0.1/libraries/base/Control/Exception.hs
--- ghc-6.0.1.orig/libraries/base/Control/Exception.hs	2003-05-12 11:16:27.000000000 +0100
+++ ghc-6.0.1/libraries/base/Control/Exception.hs	2003-09-04 18:14:06.000000000 +0100
@@ -112,7 +112,7 @@
 import GHC.Base		( assert )
 import GHC.Exception 	as ExceptionBase hiding (catch)
 import GHC.Conc		( throwTo, ThreadId )
-import GHC.IOBase	( IO(..) )
+import GHC.IOBase	( IO(..), MonadIO(..) )
 #endif
 
 #ifdef __HUGS__
@@ -173,9 +173,10 @@
 -- "Control.Exception", or importing
 -- "Control.Exception" qualified, to avoid name-clashes.
 
-catch  	:: IO a 		-- ^ The computation to run
-  	-> (Exception -> IO a)	-- ^ Handler to invoke if an exception is raised
-  	-> IO a			
+catch  	:: MonadIO m
+	=> m a			-- ^ The computation to run
+  	-> (Exception -> m a)	-- ^ Handler to invoke if an exception is raised
+  	-> m a
 catch =  ExceptionBase.catchException
 
 -- | The function 'catchJust' is like 'catch', but it takes an extra
@@ -370,10 +371,11 @@
 -- > withFile name = bracket (openFile name) hClose
 --
 bracket 
-	:: IO a		-- ^ computation to run first (\"acquire resource\")
-	-> (a -> IO b)  -- ^ computation to run last (\"release resource\")
-	-> (a -> IO c)	-- ^ computation to run in-between
-	-> IO c		-- returns the value from the in-between computation
+	:: MonadIO m
+        => m a		-- ^ computation to run first (\"acquire resource\")
+	-> (a -> m b)	-- ^ computation to run last (\"release resource\")
+	-> (a -> m c)	-- ^ computation to run in-between
+	-> m c		-- returns the value from the in-between computation
 bracket before after thing =
   block (do
     a <- before 
@@ -383,7 +385,7 @@
     after a
     return r
  )
-   
+
 
 -- | A specialised variant of 'bracket' with just a computation to run
 -- afterward.
diff -r -u ghc-6.0.1.orig/libraries/base/Control/Monad/Cont.hs ghc-6.0.1/libraries/base/Control/Monad/Cont.hs
--- ghc-6.0.1.orig/libraries/base/Control/Monad/Cont.hs	2003-05-14 18:31:47.000000000 +0100
+++ ghc-6.0.1/libraries/base/Control/Monad/Cont.hs	2003-09-04 18:46:10.000000000 +0100
@@ -77,6 +77,8 @@
 
 instance (MonadIO m) => MonadIO (ContT r m) where
 	liftIO = lift . liftIO
+	liftIO' f m = ContT $ \ k -> liftIO' f (runContT m k)
+	liftIO'' f m1 m2 = ContT $ \ k -> liftIO'' f (runContT m1 k) (\ e -> runContT (m2 e) k)
 
 instance (MonadReader r' m) => MonadReader r' (ContT r m) where
 	ask       = lift ask
diff -r -u ghc-6.0.1.orig/libraries/base/Control/Monad/Error.hs ghc-6.0.1/libraries/base/Control/Monad/Error.hs
--- ghc-6.0.1.orig/libraries/base/Control/Monad/Error.hs	2003-05-14 18:31:47.000000000 +0100
+++ ghc-6.0.1/libraries/base/Control/Monad/Error.hs	2003-09-04 18:45:18.000000000 +0100
@@ -167,6 +167,8 @@
 
 instance (Error e, MonadIO m) => MonadIO (ErrorT e m) where
 	liftIO = lift . liftIO
+	liftIO' f m = ErrorT $ liftIO' f (runErrorT m)
+	liftIO'' f m1 m2 = ErrorT $ liftIO'' f (runErrorT m1) (\ e -> runErrorT (m2 e))
 
 instance (Error e, MonadReader r m) => MonadReader r (ErrorT e m) where
 	ask       = lift ask
diff -r -u ghc-6.0.1.orig/libraries/base/Control/Monad/List.hs ghc-6.0.1/libraries/base/Control/Monad/List.hs
--- ghc-6.0.1.orig/libraries/base/Control/Monad/List.hs	2003-05-14 18:31:47.000000000 +0100
+++ ghc-6.0.1/libraries/base/Control/Monad/List.hs	2003-09-04 18:43:48.000000000 +0100
@@ -61,6 +61,8 @@
 
 instance (MonadIO m) => MonadIO (ListT m) where
 	liftIO = lift . liftIO
+	liftIO' f m = ListT $ liftIO' f (runListT m)
+	liftIO'' f m1 m2 = ListT $ liftIO'' f (runListT m1) (\ e -> runListT (m2 e))
 
 instance (MonadReader s m) => MonadReader s (ListT m) where
 	ask       = lift ask
diff -r -u ghc-6.0.1.orig/libraries/base/Control/Monad/RWS.hs ghc-6.0.1/libraries/base/Control/Monad/RWS.hs
--- ghc-6.0.1.orig/libraries/base/Control/Monad/RWS.hs	2003-05-14 18:31:47.000000000 +0100
+++ ghc-6.0.1/libraries/base/Control/Monad/RWS.hs	2003-09-04 18:43:08.000000000 +0100
@@ -142,7 +142,8 @@
 
 instance (Monoid w, MonadIO m) => MonadIO (RWST r w s m) where
 	liftIO = lift . liftIO
-
+	liftIO' f m = RWST $ \ r s -> liftIO' f (runRWST m r s)
+	liftIO'' f m1 m2 = RWST $ \ r s -> liftIO'' f (runRWST m1 r s) (\ e -> runRWST (m2 e) r s)
 
 evalRWST :: (Monad m) => RWST r w s m a -> r -> s -> m (a, w)
 evalRWST m r s = do
diff -r -u ghc-6.0.1.orig/libraries/base/Control/Monad/Reader.hs ghc-6.0.1/libraries/base/Control/Monad/Reader.hs
--- ghc-6.0.1.orig/libraries/base/Control/Monad/Reader.hs	2003-05-14 18:31:47.000000000 +0100
+++ ghc-6.0.1/libraries/base/Control/Monad/Reader.hs	2003-09-04 18:50:42.000000000 +0100
@@ -130,6 +130,8 @@
 
 instance (MonadIO m) => MonadIO (ReaderT r m) where
 	liftIO = lift . liftIO
+	liftIO' f m = ReaderT $ \ r -> liftIO' f (runReaderT m r)
+	liftIO'' f m1 m2 = ReaderT $ \ r -> liftIO'' f (runReaderT m1 r) (\ e -> runReaderT (m2 e) r)
 
 mapReaderT :: (m a -> n b) -> ReaderT w m a -> ReaderT w n b
 mapReaderT f m = ReaderT $ f . runReaderT m
diff -r -u ghc-6.0.1.orig/libraries/base/Control/Monad/State.hs ghc-6.0.1/libraries/base/Control/Monad/State.hs
--- ghc-6.0.1.orig/libraries/base/Control/Monad/State.hs	2003-05-14 18:31:47.000000000 +0100
+++ ghc-6.0.1/libraries/base/Control/Monad/State.hs	2003-09-04 18:39:29.000000000 +0100
@@ -211,6 +211,8 @@
 
 instance (MonadIO m) => MonadIO (StateT s m) where
 	liftIO = lift . liftIO
+	liftIO' f m = StateT $ \ s -> liftIO' f (runStateT m s)
+	liftIO'' f m1 m2 = StateT $ \ s -> liftIO'' f (runStateT m1 s) (\ e -> runStateT (m2 e) s)
 
 instance (MonadReader r m) => MonadReader r (StateT s m) where
 	ask       = lift ask
diff -r -u ghc-6.0.1.orig/libraries/base/Control/Monad/Trans.hs ghc-6.0.1/libraries/base/Control/Monad/Trans.hs
--- ghc-6.0.1.orig/libraries/base/Control/Monad/Trans.hs	2003-03-08 19:02:39.000000000 +0000
+++ ghc-6.0.1/libraries/base/Control/Monad/Trans.hs	2003-09-04 16:59:31.000000000 +0100
@@ -20,12 +20,13 @@
 
 module Control.Monad.Trans (
 	MonadTrans(..),
-	MonadIO(..),  
+	MonadIO(..),
   ) where
 
 import Prelude
 
 import System.IO
+import GHC.IOBase ( MonadIO(..) )
 
 -- ---------------------------------------------------------------------------
 -- MonadTrans class
@@ -36,9 +37,3 @@
 
 class MonadTrans t where
 	lift :: Monad m => m a -> t m a
-
-class (Monad m) => MonadIO m where
-	liftIO :: IO a -> m a
-
-instance MonadIO IO where
-	liftIO = id
diff -r -u ghc-6.0.1.orig/libraries/base/Control/Monad/Writer.hs ghc-6.0.1/libraries/base/Control/Monad/Writer.hs
--- ghc-6.0.1.orig/libraries/base/Control/Monad/Writer.hs	2003-05-14 18:31:47.000000000 +0100
+++ ghc-6.0.1/libraries/base/Control/Monad/Writer.hs	2003-09-04 18:39:11.000000000 +0100
@@ -142,6 +142,8 @@
 
 instance (Monoid w, MonadIO m) => MonadIO (WriterT w m) where
 	liftIO = lift . liftIO
+	liftIO' f m = WriterT $ liftIO' f (runWriterT m)
+	liftIO'' f m1 m2 = WriterT $ liftIO'' f (runWriterT m1) (\ e -> runWriterT (m2 e))
 
 instance (Monoid w, MonadReader r m) => MonadReader r (WriterT w m) where
 	ask       = lift ask
diff -r -u ghc-6.0.1.orig/libraries/base/GHC/Exception.lhs ghc-6.0.1/libraries/base/GHC/Exception.lhs
--- ghc-6.0.1.orig/libraries/base/GHC/Exception.lhs	2003-01-16 14:38:40.000000000 +0000
+++ ghc-6.0.1/libraries/base/GHC/Exception.lhs	2003-09-04 18:49:15.000000000 +0100
@@ -44,10 +44,11 @@
 have to work around that in the definition of catchException below).
 
 \begin{code}
-catchException :: IO a -> (Exception -> IO a) -> IO a
-catchException (IO m) k =  IO $ \s -> catch# m (\ex -> unIO (k ex)) s
+catchException :: MonadIO m => m a -> (Exception -> m a) -> m a
+catchException = liftIO'' catchException'
+    where catchException' (IO m) k = IO $ \s -> catch# m (\ex -> unIO (k ex)) s
 
-catch           :: IO a -> (IOError -> IO a) -> IO a 
+catch           :: MonadIO m => m a -> (IOError -> m a) -> m a
 catch m k	=  catchException m handler
   where handler (IOException err)   = k err
 	handler other               = throw other
@@ -69,17 +70,19 @@
 -- no need to worry about re-enabling asynchronous exceptions; that is
 -- done automatically on exiting the scope of
 -- 'block'.
-block :: IO a -> IO a
+block :: MonadIO m => m a -> m a
 
 -- | To re-enable asynchronous exceptions inside the scope of
 -- 'block', 'unblock' can be
 -- used.  It scopes in exactly the same way, so on exit from
 -- 'unblock' asynchronous exception delivery will
 -- be disabled again.
-unblock :: IO a -> IO a
+unblock :: MonadIO m => m a -> m a
 
-block (IO io) = IO $ blockAsyncExceptions# io
-unblock (IO io) = IO $ unblockAsyncExceptions# io
+block = liftIO' block'
+    where block' (IO io) = IO $ blockAsyncExceptions# io
+unblock = liftIO' block'
+    where block' (IO io) = IO $ unblockAsyncExceptions# io
 \end{code}
 
 
diff -r -u ghc-6.0.1.orig/libraries/base/GHC/IOBase.lhs ghc-6.0.1/libraries/base/GHC/IOBase.lhs
--- ghc-6.0.1.orig/libraries/base/GHC/IOBase.lhs	2003-05-23 12:05:33.000000000 +0100
+++ ghc-6.0.1/libraries/base/GHC/IOBase.lhs	2003-09-04 18:25:35.000000000 +0100
@@ -88,11 +88,21 @@
     m >>= k     = bindIO m k
     fail s	= failIO s
 
+class (Monad m) => MonadIO m where
+    liftIO :: IO a -> m a
+    liftIO' :: (forall a. IO a -> IO a) -> m a -> m a
+    liftIO'' :: (forall a. IO a -> (b -> IO a) -> IO a) -> m a -> (b -> m a) -> m a
+
+instance MonadIO IO where
+    liftIO = id
+    liftIO' = id
+    liftIO'' = id
+
 failIO :: String -> IO a
 failIO s = ioError (userError s)
 
-liftIO :: IO a -> State# RealWorld -> STret RealWorld a
-liftIO (IO m) = \s -> case m s of (# s', r #) -> STret s' r
+-- liftIO :: IO a -> State# RealWorld -> STret RealWorld a
+-- liftIO (IO m) = \s -> case m s of (# s', r #) -> STret s' r
 
 bindIO :: IO a -> (a -> IO b) -> IO b
 bindIO (IO m) k = IO ( \ s ->