diff -r eec5a7dcbf61 -r fcf5fb2548eb src/date.cpp
--- a/src/date.cpp	Mon Apr 14 20:32:36 2008 +0000
+++ b/src/date.cpp	Tue Apr 15 00:47:19 2008 +0000
@@ -15,6 +15,7 @@
 #include "date_func.h"
 #include "vehicle_base.h"
 #include "debug.h"
+#include "rail_gui.h"
 #ifdef DEBUG_DUMP_COMMANDS
 #include "saveload.h"
 #endif
@@ -282,6 +283,8 @@
 	ShipsYearlyLoop();
 	if (_network_server) NetworkServerYearlyLoop();
 
+	if (_cur_year == _patches.semaphore_build_before) ResetSignalVariant();
+
 	/* check if we reached end of the game */
 	if (_cur_year == _patches.ending_year) {
 			ShowEndGameChart();