diff --git a/pkgs/top-level/python-packages.nix b/pkgs/top-level/python-packages.nix
index 2087ec506f34..a34dfa5719df 100644
--- a/pkgs/top-level/python-packages.nix
+++ b/pkgs/top-level/python-packages.nix
@@ -8460,6 +8460,8 @@ in {
       sha256 = "18j1rmbmhih7q6y12grcj169q7sx1986qn4gmpla9y5gwfh1p8la";
     };
 
+    propagatedBuildInputs = with self; [ pydns ];
+
     meta = {
       homepage = "http://bmsi.com/python/milter.html";
       description = "Python API for Sendmail Milters (SPF)";