diff --git a/pkgs/servers/mail/dspam/default.nix b/pkgs/servers/mail/dspam/default.nix
index 3cd3ca7492dd..4c615e6f6b33 100644
--- a/pkgs/servers/mail/dspam/default.nix
+++ b/pkgs/servers/mail/dspam/default.nix
@@ -49,7 +49,8 @@ in stdenv.mkDerivation rec {
     "--enable-preferences-extension"
     "--enable-long-usernames"
     "--enable-external-lookup"
-  ] ++ lib.optional withMySQL "--with-mysql-includes=${libmysql}/include/mysql";
+  ] ++ lib.optional withMySQL "--with-mysql-includes=${libmysql}/include/mysql"
+    ++ lib.optional withPgSQL "--with-pgsql-libraries=${postgresql.lib}/lib";
 
   # Lots of things are hardwired to paths like sysconfdir. That's why we install with both "prefix" and "DESTDIR"
   # and fix directory structure manually after that.