diff --git a/Graphics/ImageMagick/MagickWand/WandImage.hs b/Graphics/ImageMagick/MagickWand/WandImage.hs
--- a/Graphics/ImageMagick/MagickWand/WandImage.hs
+++ b/Graphics/ImageMagick/MagickWand/WandImage.hs
@@ -910,7 +910,7 @@
 -- | Convert system specific filepath to bytestring
 _toBS = 
 #if defined(CABAL_OS_WINDOWS) || defined(CABAL_OS_DARWIN)
-    encodeUTF8
+    encodeUtf8
 #else
     id
 #endif
diff --git a/imagemagick.cabal b/imagemagick.cabal
--- a/imagemagick.cabal
+++ b/imagemagick.cabal
@@ -1,5 +1,5 @@
 Name:                imagemagick
-Version:             0.0.3
+Version:             0.0.3.1
 Synopsis:            bindings to imagemagick library
 License:             OtherLicense
 License-file:        LICENSE
@@ -75,6 +75,10 @@
                       , MonadCatchIO-transformers == 0.3.*
   extensions:         EmptyDataDecls
   Ghc-options:        -Wall
+  if os(darwin)
+        cpp-options:  -DCABAL_OS_DARWIN
+  if os(windows)
+        cpp-options:  -DCABAL_OS_WINDOWS
   pkgconfig-depends:  ImageMagick, MagickWand
   Build-tools:        hsc2hs
   if os(windows)