Add comment, use the patch for darwin

svn path=/nixpkgs/trunk/; revision=21354

pkgs/development/libraries/openssl/darwin-arch.patch

@@ -1,6 +1,4 @@
-This patch was originally added by rob.
-urkud have ported this patch to openssl-1.0.0 without diving into details (what
-does it fix etc.)
+The patch is specific to nix: MacOS gcc supports -arch.
 --- a/Configure
 +++ b/Configure
 @@ -549,9 +549,9 @@ my %table=(

pkgs/development/libraries/openssl/default.nix

@@ -6,7 +6,7 @@ let
     stdenv.cross;
 in
 
-stdenv.mkDerivation rec {
+stdenv.mkDerivation (rec {
   name = "openssl-1.0.0";
   
   src = fetchurl {
@@ -37,3 +37,9 @@ stdenv.mkDerivation rec {
     description = "A cryptographic library that implements the SSL and TLS protocols";
   };
 }
+//
+(if stdenv.isDarwin then {
+  patches = ./darwin-arch.patch;
+}
+else { })
+)