--- a/src/autoslope.h	Thu Jul 17 16:38:26 2008 +0000
+++ b/src/autoslope.h	Thu Jul 17 20:13:01 2008 +0000
@@ -39,7 +39,7 @@
 static inline bool AutoslopeEnabled()
 {
 	return (_settings_game.construction.autoslope &&
-	        ((IsValidPlayer(_current_player) && !_is_old_ai_player) ||
+	        ((IsValidPlayerID(_current_player) && !_is_old_ai_player) ||
 	         (_current_player == OWNER_NONE && _game_mode == GM_EDITOR)));
 }