diff --git a/docs/setup-example.nix b/docs/setup-example.nix
index 66a8242..0894a94 100644
--- a/docs/setup-example.nix
+++ b/docs/setup-example.nix
@@ -29,7 +29,7 @@
 
   mailserver = {
     enable = true;
-    stateVersion = 3;
+    stateVersion = 4;
     fqdn = "mail.example.com";
     domains = [ "example.com" ];