diff --git a/pkgs/development/libraries/ilmbase/default.nix b/pkgs/development/libraries/ilmbase/default.nix
index 0244725177e6..4ea16a59e8b4 100644
--- a/pkgs/development/libraries/ilmbase/default.nix
+++ b/pkgs/development/libraries/ilmbase/default.nix
@@ -18,9 +18,6 @@ stdenv.mkDerivation rec {
     ./bootstrap
   '';
 
-  # otherwise, the pkgconfig info for the libraries will not match the filenames
-  configureFlags = stdenv.lib.optionalString stdenv.isDarwin "--enable-namespaceversioning=no";
-  
   depsBuildBuild = [ buildPackages.stdenv.cc ];
   nativeBuildInputs = [ automake autoconf libtool which ];
 
diff --git a/pkgs/development/libraries/openexr/default.nix b/pkgs/development/libraries/openexr/default.nix
index 81a5ab1db992..da8fb4294650 100644
--- a/pkgs/development/libraries/openexr/default.nix
+++ b/pkgs/development/libraries/openexr/default.nix
@@ -42,9 +42,6 @@ stdenv.mkDerivation rec {
     ./bootstrap
   '';
 
-  # otherwise, the pkgconfig info for the libraries will not match the filenames
-  configureFlags = stdenv.lib.optionalString stdenv.isDarwin "--enable-namespaceversioning=no";
-
   nativeBuildInputs = [ pkgconfig autoconf automake libtool ];
   propagatedBuildInputs = [ ilmbase zlib ];