diff --git a/Data/Void.hs b/Data/Void.hs
--- a/Data/Void.hs
+++ b/Data/Void.hs
@@ -38,19 +38,19 @@
 #endif
   )
 
--- | Since Void values are logically uninhabited, this witnesses the logical
--- reasoning tool of 'ex falso quodlibet'.
+-- | Since 'Void' values logically don't exist, this witnesses the logical
+-- reasoning tool of \"ex falso quodlibet\".
 absurd :: Void -> a
 absurd a = a `seq` spin a where
    spin (Void b) = spin b
 
--- | If 'Void' is uninhabited then any 'Functor' that holds values of type 'Void'
+-- | If 'Void' is uninhabited then any 'Functor' that holds only values of type 'Void'
 -- is holding no values.
 vacuous :: Functor f => f Void -> f a
 #ifdef __GLASGOW_HASKELL__
 vacuous = unsafeCoerce
 #else
--- other haskell compilers are free to use less homogeneous representations
+-- other haskell compilers are free to use less homogeneous representations (NHC does, for instance)
 vacuous = fmap absurd
 #endif
 
diff --git a/void.cabal b/void.cabal
--- a/void.cabal
+++ b/void.cabal
@@ -1,6 +1,6 @@
 name:          void
 category:      Data Structures
-version:       0.5.7
+version:       0.5.8
 license:       BSD3
 cabal-version: >= 1.6
 license-file:  LICENSE
@@ -9,9 +9,9 @@
 stability:     portable
 homepage:      http://github.com/ekmett/void
 bug-reports:   http://github.com/ekmett/void/issues
-copyright:     Copyright (C) 2008-2011 Edward A. Kmett
+copyright:     Copyright (C) 2008-2012 Edward A. Kmett
 synopsis:      A Haskell 98 logically uninhabited data type
-description:   A Haskell 98 logically uninhabited data type. Used to indicate that a given term should not exist.
+description:   A Haskell 98 logically uninhabited data type, used to indicate that a given term should not exist.
 build-type:    Simple
 
 extra-source-files: .travis.yml
@@ -20,10 +20,6 @@
   type: git
   location: git://github.com/ekmett/void.git
 
-flag DeriveDataTypeable
-  manual: False
-  default: True
-
 library
   extensions:
     CPP
@@ -35,6 +31,6 @@
 
   ghc-options: -Wall
 
-  if flag(DeriveDataTypeable)
+  if impl(ghc)
     extensions: DeriveDataTypeable
     cpp-options: -DLANGUAGE_DeriveDataTypeable