diff --git a/Storage/Hashed/Test.hs b/Storage/Hashed/Test.hs
index d3cab6f..7f8291e 100644
--- a/Storage/Hashed/Test.hs
+++ b/Storage/Hashed/Test.hs
@@ -1,2 +1,2 @@
-{-# LANGUAGE ScopedTypeVariables, FlexibleInstances #-}
+{-# LANGUAGE ScopedTypeVariables, FlexibleInstances, CPP #-}
 module Storage.Hashed.Test( tests ) where
@@ -464,2 +464,3 @@ posix = [ testCase "getFileStatus" $ check_stat Posix.getFileStatus
 
+#if ! MIN_VERSION_QuickCheck(2,8,2)
 instance (Arbitrary a, Ord a) => Arbitrary (S.Set a)
@@ -469,2 +470,3 @@ instance (Arbitrary k, Arbitrary v, Ord k) => Arbitrary (M.Map k v)
     where arbitrary = M.fromList `fmap` arbitrary
+#endif