qt4: Override broken installPhase on Darwin

pkgs/development/libraries/qt-4.x/4.8/default.nix

@@ -183,10 +183,38 @@ stdenv.mkDerivation rec {
     sed -i 's/^\(LIBS[[:space:]]*=.*$\)/\1 -lobjc/' ./src/corelib/Makefile.Release
   '';
 
-  postInstall =
+  installPhase = optionalString stdenv.isDarwin ''
-    ''
+    runHook preInstall
+    cp -r lib $out
+
+    mkdir -p $out/Applications
+    mv bin/*.app $out/Applications
+    rm -rf bin/*.app
+
+    cp -r bin $out
+
+    mkdir -p $out/share/doc/${name}
+    mkdir -p $out/lib
+    mkdir -p $out/lib/qt4/plugins
+    mkdir -p $out/lib/qt4/imports
+    mkdir -p $out/bin
+    mkdir -p $out/include
+    mkdir -p $out/share/${name}
+
+    cp -r mkspecs $out/share/${name}
+    cp -r translations $out/share/${name}
+    cp -r tools/linguist/phrasebooks $out/share/${name}
+    cp tools/porting/src/q3porting.xml $out/share/${name}
+
+    cp -r plugins $out/lib/qt4
+    cp -r imports $out/lib/qt4
+    cp -r doc/* $out/share/doc/${name}
+    runHook postInstall
+  '';
+
+  postInstall = optionalString (!stdenv.isDarwin) ''
       rm -rf $out/tests
-    '';
+  '';
 
   crossAttrs = {
     # I've not tried any case other than i686-pc-mingw32.