diff --git a/pkgs/development/libraries/libmilter/default.nix b/pkgs/development/libraries/libmilter/default.nix
index 8d677d858de8..60ced27beac7 100644
--- a/pkgs/development/libraries/libmilter/default.nix
+++ b/pkgs/development/libraries/libmilter/default.nix
@@ -28,6 +28,7 @@ stdenv.mkDerivation rec {
       define(\`confLIBGRP', \`root')
       APPENDDEF(\`confENVDEF', \`-DNETINET6')
     EOF
+    export MILTER_SOVER=1
     sh Build -f ./a.m4
   '';