diff --git a/threefish.cabal b/threefish.cabal
--- a/threefish.cabal
+++ b/threefish.cabal
@@ -1,5 +1,5 @@
 name:                threefish
-version:             0.2.2
+version:             0.2.3
 synopsis:            The Threefish block cipher and the Skein hash function for Haskell.
 description:         Implements 256 and 512 bit variants of Threefish and Skein. Skein is usable as a "normal" hash function as well as in Skein-MAC, as a cryptographically secure PRNG, as a stream cipher and as a key derivation function, all implemented according to the specifications of the Skein 1.3 paper.
 homepage:            http://github.com/valderman/threefish
@@ -49,6 +49,8 @@
   default-language:    Haskell2010
   ghc-options: -Wall -O2
   include-dirs: cbits
+  includes:
+    threefish.h
   c-sources:
     cbits/threefish256.c,
     cbits/skein256.c,