diff --git a/Data/RefSerialize.hs b/Data/RefSerialize.hs
--- a/Data/RefSerialize.hs
+++ b/Data/RefSerialize.hs
@@ -239,7 +239,7 @@
       return $ runWC (c,"") f `append` showContext c True
 
 -- | serialize x witn a given context and the parser
-runWC ::(Context, ByteString) -> STW () -> ByteString
+runWC :: (Context, ByteString) -> STW () -> ByteString
 runWC (c,vars) (STW f) =
       let
           (StatW(c',str,_), _) = f (StatW(c,[],vars))
@@ -366,7 +366,7 @@
   trytofindEntireObject x c=
          case Data.RefSerialize.Serialize.lookup  hash  c  of
            Nothing -> Nothing
-           Just(x,y,z,n)  -> insert hash (x,y,z,n+1) `seq` Just varname
+           Just(x,y,z,n)  -> insert hash (x,y,z,n+1) c `seq` Just varname
 
 
 
diff --git a/Data/RefSerialize/Serialize.hs b/Data/RefSerialize/Serialize.hs
--- a/Data/RefSerialize/Serialize.hs
+++ b/Data/RefSerialize/Serialize.hs
@@ -15,15 +15,15 @@
 import System.IO.Unsafe
 import Control.Monad (MonadPlus(..))
 import Data.ByteString.Lazy.Char8 as B
-import qualified Data.HashTable  as HT
-
+--import qualified Data.HashTable  as HT
+import qualified Data.HashTable.IO as HT
 import Data.Ord
 
 
 type MFun=  Char -- usafeCoherced to char to store simply the address of the function
 type VarName = String
 data ShowF= Expr ByteString | Var Int  deriving Show
-type Context =  HT.HashTable Int (  StableName MFun, MFun,[ShowF],Int)
+type Context =  HT.BasicHashTable Int (  StableName MFun, MFun,[ShowF],Int)
 
 data Error= Error String
 data StatW= StatW (Context, [ShowF], ByteString)
@@ -45,12 +45,12 @@
 
 
 -- HT to map
-empty  =    HT.new (==) HT.hashInt
+empty  =    HT.new -- (==) HT.hashInt
 
 assocs = sortBy (comparing fst) . unsafePerformIO . HT.toList
 
 
-insert  k v ht= unsafePerformIO $! HT.update ht k v >> return ht
+insert  k v ht= unsafePerformIO $! HT.insert ht k v >> return ht
 
 
 
@@ -63,7 +63,7 @@
 toList  = unsafePerformIO . HT.toList
 
 
-fromList = unsafePerformIO . HT.fromList HT.hashInt
+fromList = unsafePerformIO . HT.fromList -- HT.hashInt
 
 -- | return a unique hash identifier for an object
 -- the context assures that no StableName used in addrStr is garbage collected,
@@ -74,9 +74,9 @@
 addrHash c x =
   case  Data.RefSerialize.Serialize.lookup  hash  c  of
            Nothing -> addc [Var hash] c >>  return (Left hash)
-           Just (x,y,z,n)  -> HT.update c hash (x,y,z,n+1) >> return (Right hash)
+           Just (x,y,z,n)  -> HT.insert c hash (x,y,z,n+1) >> return (Right hash)
   where
-  addc str c=  HT.update c hash (st,unsafeCoerce x,  str,1)
+  addc str c=  HT.insert c hash (st,unsafeCoerce x,  str,1)
   (hash,st) = hasht x
 
 readContext :: ByteString -> ByteString -> (ByteString, ByteString)
diff --git a/RefSerialize.cabal b/RefSerialize.cabal
--- a/RefSerialize.cabal
+++ b/RefSerialize.cabal
@@ -1,5 +1,5 @@
 name:                RefSerialize
-version:             0.3.1.0
+version:             0.3.1.1
 synopsis:            Write to and read from ByteStrings maintaining internal memory references
 description:
                      Read, Show and Binary instances do not check for internal data references to the same address.
@@ -22,7 +22,7 @@
 maintainer:           agocorona@gmail.com
 Tested-With:        GHC == 6.8.2
 Build-Type:          Simple
-build-Depends:      binary,bytestring, base >=4 && <5,containers
+build-Depends:      binary,bytestring, base >=4 && <5,containers, hashtables
 
 
 exposed-modules:     Data.RefSerialize, Data.RefSerialize.Parser, Data.RefSerialize.Serialize