diff --git a/Data/Collections.hs b/Data/Collections.hs
--- a/Data/Collections.hs
+++ b/Data/Collections.hs
@@ -742,7 +742,7 @@
     difference = Map.difference
     delete = Map.delete
     intersection = Map.intersection
-    lookup = Map.lookup
+    lookup x y = lifted $ Map.lookup x y
     alter = Map.alter
     insertWith = Map.insertWith
     unionWith = Map.unionWith
@@ -751,9 +751,13 @@
     mapWithKey = Map.mapWithKey
 
 instance Ord k => SortingCollection (Map.Map k a) (k,a) where
-    minView x = return swap `ap` Map.minView x
+    minView x = lifted $ Map.minViewWithKey x
         where swap (x,y) = (y,x)
 
+lifted :: Monad m => Maybe a -> m a
+lifted action = 
+    case action of Nothing -> fail "missing key (probably)" ; Just x -> return x
+
 -----------------------------------------------------------------------------
 -- Data.AvlMap
 instance Foldable (AvlMap.Map k a) (k,a) where
@@ -822,7 +826,7 @@
     difference = IntMap.difference
     delete = IntMap.delete
     intersection = IntMap.intersection
-    lookup = IntMap.lookup
+    lookup x y = lifted $ IntMap.lookup x y
     alter = IntMap.alter
     insertWith = IntMap.insertWith
     unionWith = IntMap.unionWith
diff --git a/Data/Collections/Properties.hs b/Data/Collections/Properties.hs
--- a/Data/Collections/Properties.hs
+++ b/Data/Collections/Properties.hs
@@ -84,6 +84,8 @@
 
 infix 1 <==
 
+{- 
+-- no longer needed since this is in quickcheck now
 instance Arbitrary a => Arbitrary (Maybe a)
     where arbitrary = do test <- arbitrary
                          if test 
@@ -91,6 +93,7 @@
                             else return Just `ap` arbitrary
           coarbitrary Nothing = variant 0
           coarbitrary (Just x) = variant 1 . coarbitrary x
+-}
 
 instance Show (a->b) where
     show _ = "<func>"
diff --git a/Data/Ranged/Ranges.hs b/Data/Ranged/Ranges.hs
--- a/Data/Ranged/Ranges.hs
+++ b/Data/Ranged/Ranges.hs
@@ -1,5 +1,5 @@
 {-# OPTIONS_GHC -cpp -fglasgow-exts #-}
------------------------------------------------------------------------------
+
 -- |
 -- Module      :  Data.Ranged.Ranges
 -- Copyright   :  (c) Paul Johnson 2006
@@ -7,11 +7,8 @@
 -- Maintainer  :  paul@cogito.org.uk
 -- Stability   :  experimental
 -- Portability :  portable
---
------------------------------------------------------------------------------
-
+-- A range has an upper and lower boundary.
 
--- | A range has an upper and lower boundary.
 module Data.Ranged.Ranges (
    -- ** Construction
    Range (..),
diff --git a/Data/Trie.hs b/Data/Trie.hs
--- a/Data/Trie.hs
+++ b/Data/Trie.hs
@@ -117,9 +117,9 @@
 toMaybe f b = if f b then Nothing else Just b
 
 alter :: forall s k v. (C.Foldable s k, Ord k) => (Maybe v -> Maybe v) -> s -> Trie s k v -> Trie s k v
-alter f s t = C.foldr rec zero s t
+alter f s t = C.foldr rek zero s t
     where zero (Trie v cs) = (Trie (f v) cs) 
-          rec k sub (Trie v cs) = Trie v (C.alter (f' sub) k cs)
+          rek k sub (Trie v cs) = Trie v (C.alter (f' sub) k cs)
           f' sub t = toMaybe null (sub (fromMaybe empty t))
           -- recursive application: need to "create" empty nodes in case f creates a leaf node.
 
@@ -131,10 +131,10 @@
 --           f' ks (Just t) = toMaybe (alter f ks t)
 
 adjust :: forall s k v. (C.Foldable s k, Ord k) => (v -> v) -> s -> Trie s k v -> Trie s k v
-adjust f s t = C.foldr rec zero s t
+adjust f s t = C.foldr rek zero s t
     where zero t@(Trie Nothing _) = t
           zero (Trie (Just v) cs) = (Trie (Just (f v)) cs) 
-          rec k sub (Trie v cs) = Trie v (C.adjust sub k cs)
+          rek k sub (Trie v cs) = Trie v (C.adjust sub k cs)
         
 -- | Modify the 'children' field of a trie.
 value_u :: (Maybe v -> Maybe v) -> Trie s k v -> Trie s k v
diff --git a/collections.cabal b/collections.cabal
--- a/collections.cabal
+++ b/collections.cabal
@@ -1,5 +1,5 @@
 name:		collections
-version:	0.3
+version:	0.3.1
 category:       Data Structures
 description:    
         This package provides a suite of data structures types, with a consistent API. 
@@ -48,6 +48,7 @@
 	Data.Tree.AVL.Internals.HeightUtils
 include-dirs: 	include
 extra-source-files: include/Typeable.h include/ghcdefs.h include/h98defs.h
-build-depends:	base >= 2.0, QuickCheck
+build-type: Simple
+build-depends:	base >=3 && < 4, QuickCheck, containers, array, bytestring
 extensions:	CPP
-ghc-options:    -O -Wall -fno-warn-name-shadowing -fno-warn-incomplete-patterns
+ghc-options:    -Wall -fno-warn-name-shadowing -fno-warn-incomplete-patterns