diff --git a/mailserver.nix b/mailserver.nix
index 6ec6b6e..6d9a121 100644
--- a/mailserver.nix
+++ b/mailserver.nix
@@ -1,5 +1,12 @@
 { config, pkgs, ... }:
 
+let
+  spamfilter_greenlight_map = pkgs.writeText "spamfilter_greenlight_map.cf" ''
+    # Disable Milters for specific clients
+    2a00:14b0:4200:3000:122::1/128    DISABLE
+    212.12.48.122/32                  DISABLE
+    '';
+in
 {
   # Import some configuration as they are too long to be easily readable here
   imports = [ 
@@ -17,4 +24,8 @@
     adminAddress = "postmaster@mail.hamburg.freifunk.net";
     mailFQDN = "mail2.hamburg.freifunk.net";
   };
+  # Special config
+  services.postfix.config = {
+    smtpd_milter_maps = "cidr:${spamfilter_greenlight_map}";
+  };
 }