(svn r3403) -Codechange: [multiheaded engines] the references between the front and rear engines are no longer saved

instead the pointers are generated on load

openttd.c

@@ -40,6 +40,7 @@
 #include "depot.h"
 #include "waypoint.h"
 #include "ai/ai.h"
+#include "train.h"
 
 #include <stdarg.h>
 
@@ -1144,6 +1145,10 @@ bool AfterLoadGame(void)
 	 * subtype to the new format */
 	if (CheckSavegameVersionOldStyle(17, 1)) ConvertOldMultiheadToNew();
 
+	/* Connect front and rear engines of multiheaded trains
+		since this info were no longer saved in savegame version 20 */
+	if (!CheckSavegameVersion(20)) ConnectMultiheadedTrains();
+
 	// Update current year
 	SetDate(_date);