diff --git a/hoauth.cabal b/hoauth.cabal
--- a/hoauth.cabal
+++ b/hoauth.cabal
@@ -1,5 +1,5 @@
 name: hoauth
-version: 0.1.6
+version: 0.1.7
 category: Network,Protocol,OAuth
 license: BSD3
 license-file: LICENSE
diff --git a/src/main/haskell/Network/Protocol/OAuth/Signature.hs b/src/main/haskell/Network/Protocol/OAuth/Signature.hs
--- a/src/main/haskell/Network/Protocol/OAuth/Signature.hs
+++ b/src/main/haskell/Network/Protocol/OAuth/Signature.hs
@@ -30,7 +30,6 @@
 import qualified Network.Protocol.OAuth.Request as R
 import qualified Data.Digest.Pure.SHA  as S
 import qualified Data.Char as C
-import qualified Data.ByteString.Lazy as B
 import qualified Data.ByteString.Lazy.Char8 as B1
 import qualified Codec.Binary.Base64.String as B2
 import qualified Codec.Crypto.RSA as R1
@@ -72,9 +71,9 @@
   sign (PLAINTEXT k (Just s)) _ = k ++ "&" ++ s
   sign (PLAINTEXT k Nothing)  _ = k ++ "&"
 
-  sign (HMAC_SHA1 k Nothing)  r = let secret = B.concat [R.encodes k, _froms "&"]
+  sign (HMAC_SHA1 k Nothing)  r = let secret = B1.concat [R.encodes k, _froms "&"]
                                   in (B2.encode . B1.unpack . S.bytestringDigest . S.hmacSha1 secret . _basestr) r
-  sign (HMAC_SHA1 k (Just s)) r = let secret = B.concat [R.encodes k, _froms "&", R.encodes s]
+  sign (HMAC_SHA1 k (Just s)) r = let secret = B1.concat [R.encodes k, _froms "&", R.encodes s]
                                   in (B2.encode . B1.unpack . S.bytestringDigest . S.hmacSha1 secret . _basestr) r
 
   sign (RSA_SHA1 k) r           = (B2.encode . B1.unpack . R1.rsassa_pkcs1_v1_5_sign R1.ha_SHA1 k . _basestr) r
@@ -86,11 +85,11 @@
 
   showsPrec _ (RSA_SHA1 _)    = showString "RSA-SHA1"
 
-_basestr :: R.Request -> B.ByteString
+_basestr :: R.Request -> B1.ByteString
 _basestr r = let endpoint' = (R.encodes . _endpoint) r
                  params'   = (R.encodes . _params) r
                  method'   = (R.encodes . show . R.method) r
-             in B.concat [method', _froms "&", endpoint', _froms "&", params']
+             in B1.concat [method', _froms "&", endpoint', _froms "&", params']
 
 _endpoint :: R.Request -> String
 _endpoint r | R.ssl r   = ssl_endpoint'
@@ -107,8 +106,8 @@
                   | otherwise       = "http://" ++ host' ++ port' ++ (R.path r)
 
 _params :: R.Request -> String
-_params = map (C.chr . fromIntegral) . B.unpack . R.show_urlencoded . R.params
+_params = B1.unpack . R.show_urlencoded . R.params
 
-_froms :: String -> B.ByteString
-_froms = B.pack . map (fromIntegral . C.ord)
+_froms :: String -> B1.ByteString
+_froms = B1.pack