diff --git a/List.cabal b/List.cabal
--- a/List.cabal
+++ b/List.cabal
@@ -1,5 +1,5 @@
 Name:                List
-Version:             0.4.3
+Version:             0.4.4
 Category:            Control
 Synopsis:            List monad transformer and class
 Description:
diff --git a/src/Data/List/Class.hs b/src/Data/List/Class.hs
--- a/src/Data/List/Class.hs
+++ b/src/Data/List/Class.hs
@@ -15,7 +15,10 @@
     concat, concatMap,
     tail,
     enumFrom, enumFromTo,
-    catMaybes, mapMaybe,
+    catMaybes,
+    -- mapMaybe will be reintroduced in List-0.5.0
+    -- Removed from List-0.4.4 to unbreak hexpat-0.20.2
+    -- Which broke with the release of List-0.4.3 due to unqualified imports.
     -- | Non standard List operations
     foldrL, foldlL, foldl1L, toList, lengthL, lastL,
     merge2On, mergeOn,
@@ -351,8 +354,9 @@
         f Nothing = mzero
         f (Just x) = return x
 
-mapMaybe :: List l => (a -> Maybe b) -> l a -> l b
-mapMaybe f = catMaybes . liftM f
+-- To be reintroduced in List 0.5.0
+-- mapMaybe :: List l => (a -> Maybe b) -> l a -> l b
+-- mapMaybe f = catMaybes . liftM f
 
 enumFrom :: (List l, Enum a) => a -> l a
 enumFrom x = cons x (enumFrom (succ x))