diff -r 4b963391b435 -r 7d0fac8f14cd src/town_gui.cpp
--- a/src/town_gui.cpp	Thu Jul 17 16:38:26 2008 +0000
+++ b/src/town_gui.cpp	Thu Jul 17 20:13:01 2008 +0000
@@ -781,7 +781,7 @@
 
 void ShowBuildTownWindow()
 {
-	if (_game_mode != GM_EDITOR && !IsValidPlayer(_current_player)) return;
+	if (_game_mode != GM_EDITOR && !IsValidPlayerID(_current_player)) return;
 	AllocateWindowDescFront<ScenarioEditorTownGenerationWindow>(&_scen_edit_town_gen_desc, 0);
 }