Index: ai/trolly/trolly.c
===================================================================
--- ai/trolly/trolly.c	(revision 7622)
+++ ai/trolly/trolly.c	(working copy)
@@ -81,7 +81,7 @@
 {
 	assert(p->ainew.state == AI_STATE_NOTHING);
 	// If we are done idling, start over again
-	if (p->ainew.idle == 0) p->ainew.idle = AI_RandomRange(DAY_TICKS * 2) + DAY_TICKS;
+	if (p->ainew.idle == 0) p->ainew.idle = AI_RandomRange((DAY_TICKS/_patches.day_length) * 2) + (DAY_TICKS/_patches.day_length);
 	if (--p->ainew.idle == 0) {
 		// We are done idling.. what you say? Let's do something!
 		// I mean.. the next tick ;)
@@ -877,7 +877,7 @@
 		// Passenger run.. how long is the route?
 		length = p->ainew.path_info.route_length;
 		// Calculating tiles a day a vehicle moves is not easy.. this is how it must be done!
-		tiles_a_day = RoadVehInfo(i)->max_speed * DAY_TICKS / 256 / 16;
+		tiles_a_day = RoadVehInfo(i)->max_speed * (DAY_TICKS/_patches.day_length) / 256 / 16;
 		// We want a vehicle in a station once a month at least, so, calculate it!
 		// (the * 2 is because we have 2 stations ;))
 		amount = length * 2 * 2 / tiles_a_day / 30;
@@ -893,7 +893,7 @@
 		// Passenger run.. how long is the route?
 		length = p->ainew.path_info.route_length;
 		// Calculating tiles a day a vehicle moves is not easy.. this is how it must be done!
-		tiles_a_day = RoadVehInfo(i)->max_speed * DAY_TICKS / 256 / 16;
+		tiles_a_day = RoadVehInfo(i)->max_speed * (DAY_TICKS/_patches.day_length) / 256 / 16;
 		if (p->ainew.from_deliver) {
 			max_cargo = GetIndustry(p->ainew.from_ic)->total_production[0];
 		} else {
Index: ai/trolly/trolly.h
===================================================================
--- ai/trolly/trolly.h	(revision 7622)
+++ ai/trolly/trolly.h	(working copy)
@@ -139,7 +139,7 @@
 #define AI_CHECK_MAX_VEHICLE_PER_STATION 10
 
 // How many thick between building 2 vehicles
-#define AI_BUILD_VEHICLE_TIME_BETWEEN DAY_TICKS
+#define AI_BUILD_VEHICLE_TIME_BETWEEN (DAY_TICKS/_patches.day_length)
 
 // How many days must there between vehicle checks
 //  The more often, the less non-money-making lines there will be
Index: aircraft_cmd.c
===================================================================
--- aircraft_cmd.c	(revision 7622)
+++ aircraft_cmd.c	(working copy)
@@ -708,7 +708,7 @@
 
 	if (v->vehstatus & VS_STOPPED) return;
 
-	cost = AircraftVehInfo(v->engine_type)->running_cost * _price.aircraft_running / 364;
+	cost = AircraftVehInfo(v->engine_type)->running_cost * (_patches.daylength_affect_economy?_patches.day_length:1) * _price.aircraft_running / 364;
 
 	v->profit_this_year -= cost >> 8;
 
Index: build_vehicle_gui.c
===================================================================
--- build_vehicle_gui.c	(revision 7622)
+++ build_vehicle_gui.c	(working copy)
@@ -230,7 +230,7 @@
 	y += 10;
 
 	/* Running cost */
-	SetDParam(0, avi->running_cost * _price.aircraft_running >> 8);
+	SetDParam(0, avi->running_cost * (_patches.daylength_affect_economy?_patches.day_length:1) * _price.aircraft_running >> 8);
 	DrawString(x, y, STR_PURCHASE_INFO_RUNNINGCOST, 0);
 	y += 10;
 
Index: date.c
===================================================================
--- date.c	(revision 7622)
+++ date.c	(working copy)
@@ -199,7 +199,7 @@
 	uint total = GetMaxVehicleIndex() + 1;
 	uint i;
 
-	for (i = daytick; i < total; i += DAY_TICKS) {
+	for (i = daytick; i < total; i += (DAY_TICKS*_patches.day_length)) {
 		Vehicle *v = GetVehicle(i);
 
 		if (IsValidVehicle(v)) _on_new_vehicle_day_proc[v->type - 0x10](v);
@@ -221,7 +221,7 @@
 	_tick_counter++;
 
 	_date_fract++;
-	if (_date_fract < DAY_TICKS) return;
+	if (_date_fract < (DAY_TICKS*_patches.day_length)) return;
 	_date_fract = 0;
 
 	/* yeah, increase day counter and call various daily loops */
Index: engine_gui.c
===================================================================
--- engine_gui.c	(revision 7622)
+++ engine_gui.c	(working copy)
@@ -128,7 +128,7 @@
 	SetDParam(3, rvi->power << multihead);
 	SetDParam(1, rvi->weight << multihead);
 
-	SetDParam(4, rvi->running_cost_base * _price.running_rail[rvi->running_cost_class] >> 8 << multihead);
+	SetDParam(4, rvi->running_cost_base * _price.running_rail[rvi->running_cost_class] * (_patches.daylength_affect_economy?_patches.day_length:1) >> 8 << multihead);
 
 	if (rvi->capacity != 0) {
 		SetDParam(5, rvi->cargo_type);
@@ -175,7 +175,7 @@
 	SetDParam(1, avi->max_speed * 128 / 10);
 	SetDParam(2, avi->passenger_capacity);
 	SetDParam(3, avi->mail_capacity);
-	SetDParam(4, avi->running_cost * _price.aircraft_running >> 8);
+	SetDParam(4, avi->running_cost * (_patches.daylength_affect_economy?_patches.day_length:1) * _price.aircraft_running >> 8);
 
 	DrawStringMultiCenter(x, y, STR_A02E_COST_MAX_SPEED_CAPACITY, maxw);
 }
@@ -213,7 +213,7 @@
 
 	SetDParam(0, (_price.roadveh_base >> 3) * rvi->base_cost >> 5);
 	SetDParam(1, rvi->max_speed / 2);
-	SetDParam(2, rvi->running_cost * _price.roadveh_running >> 8);
+	SetDParam(2, rvi->running_cost * (_patches.daylength_affect_economy?_patches.day_length:1) * _price.roadveh_running >> 8);
 	SetDParam(3, rvi->cargo_type);
 	SetDParam(4, rvi->capacity);
 
@@ -253,7 +253,7 @@
 	SetDParam(1, svi->max_speed / 2);
 	SetDParam(2, svi->cargo_type);
 	SetDParam(3, svi->capacity);
-	SetDParam(4, svi->running_cost * _price.ship_running >> 8);
+	SetDParam(4, svi->running_cost * (_patches.daylength_affect_economy?_patches.day_length:1) * _price.ship_running >> 8);
 	DrawStringMultiCenter(x, y, STR_982E_COST_MAX_SPEED_CAPACITY, maxw);
 }
 
Index: graph_gui.c
===================================================================
--- graph_gui.c	(revision 7622)
+++ graph_gui.c	(working copy)
@@ -1051,7 +1051,7 @@
 				if (p2->is_active) UpdateCompanyRatingAndValue(p2, false);
 			}
 
-			w->custom[0] = DAY_TICKS;
+			w->custom[0] = (DAY_TICKS/_patches.day_length);
 			w->custom[1] = 5;
 
 			_performance_rating_detail_player = 0;
@@ -1064,7 +1064,7 @@
 		case WE_TICK: {
 			// Update the player score every 5 days
 			if (--w->custom[0] == 0) {
-				w->custom[0] = DAY_TICKS;
+				w->custom[0] = (DAY_TICKS/_patches.day_length);
 				if (--w->custom[1] == 0) {
 					Player *p2;
 
Index: lang/english.txt
===================================================================
--- lang/english.txt	(revision 7622)
+++ lang/english.txt	(working copy)
@@ -1123,6 +1123,8 @@
 STR_CONFIG_PATCHES_TOOLBAR_POS_RIGHT                            :Right
 STR_CONFIG_PATCHES_SNAP_RADIUS                                  :{LTBLUE}Window snap radius: {ORANGE}{STRING1} px
 STR_CONFIG_PATCHES_SNAP_RADIUS_DISABLED                         :{LTBLUE}Window snap radius: {ORANGE}disabled
+STR_CONFIG_PATCHES_DAY_LENGTH                                   :{LTBLUE}Default day length: {ORANGE}{STRING1}
+STR_CONFIG_PATCHES_DAY_LENGTH_ECONOMY                           :{LTBLUE}Day length affect economy: {ORANGE}{STRING1}
 
 STR_CONFIG_PATCHES_GUI                                          :{BLACK}Interface
 STR_CONFIG_PATCHES_CONSTRUCTION                                 :{BLACK}Construction
Index: network.c
===================================================================
--- network.c	(revision 7622)
+++ network.c	(working copy)
@@ -121,7 +121,7 @@
 {
 	char buf[1024];
 	va_list va;
-	const int duration = 10; // Game days the messages stay visible
+	const int duration = 10/_patches.day_length; // Game days the messages stay visible
 	char message[1024];
 	char temp[1024];
 
@@ -188,11 +188,11 @@
 uint NetworkCalculateLag(const NetworkClientState *cs)
 {
 	int lag = cs->last_frame_server - cs->last_frame;
-	// This client has missed his ACK packet after 1 DAY_TICKS..
+	// This client has missed his ACK packet after 1 (DAY_TICKS/_patches.day_length)..
 	//  so we increase his lag for every frame that passes!
 	// The packet can be out by a max of _net_frame_freq
-	if (cs->last_frame_server + DAY_TICKS + _network_frame_freq < _frame_counter)
-		lag += _frame_counter - (cs->last_frame_server + DAY_TICKS + _network_frame_freq);
+	if (cs->last_frame_server + (DAY_TICKS/_patches.day_length) + _network_frame_freq < _frame_counter)
+		lag += _frame_counter - (cs->last_frame_server + (DAY_TICKS/_patches.day_length) + _network_frame_freq);
 
 	return lag;
 }
Index: network_client.c
===================================================================
--- network_client.c	(revision 7622)
+++ network_client.c	(working copy)
@@ -548,7 +548,7 @@
 	// Let the server know that we received this frame correctly
 	//  We do this only once per day, to save some bandwidth ;)
 	if (!_network_first_time && last_ack_frame < _frame_counter) {
-		last_ack_frame = _frame_counter + DAY_TICKS;
+		last_ack_frame = _frame_counter + (DAY_TICKS/_patches.day_length);
 		DEBUG(net, 4, "Sent ACK at %d", _frame_counter);
 		SEND_COMMAND(PACKET_CLIENT_ACK)();
 	}
Index: network_server.c
===================================================================
--- network_server.c	(revision 7622)
+++ network_server.c	(working copy)
@@ -950,7 +950,7 @@
 	/* The client is trying to catch up with the server */
 	if (cs->status == STATUS_PRE_ACTIVE) {
 		/* The client is not yet catched up? */
-		if (frame + DAY_TICKS < _frame_counter) return;
+		if (frame + (DAY_TICKS/_patches.day_length) < _frame_counter) return;
 
 		/* Now he is! Unpause the game */
 		cs->status = STATUS_ACTIVE;
@@ -1470,7 +1470,7 @@
 		// Check if the speed of the client is what we can expect from a client
 		if (cs->status == STATUS_ACTIVE) {
 			// 1 lag-point per day
-			int lag = NetworkCalculateLag(cs) / DAY_TICKS;
+			int lag = NetworkCalculateLag(cs) / (DAY_TICKS/_patches.day_length);
 			if (lag > 0) {
 				if (lag > 3) {
 					// Client did still not report in after 4 game-day, drop him
Index: roadveh_cmd.c
===================================================================
--- roadveh_cmd.c	(revision 7622)
+++ roadveh_cmd.c	(working copy)
@@ -1716,7 +1716,7 @@
 		}
 	}
 
-	cost = RoadVehInfo(v->engine_type)->running_cost * _price.roadveh_running / 364;
+	cost = RoadVehInfo(v->engine_type)->running_cost * (_patches.daylength_affect_economy?_patches.day_length:1) * _price.roadveh_running / 364;
 
 	v->profit_this_year -= cost >> 8;
 
Index: roadveh_gui.c
===================================================================
--- roadveh_gui.c	(revision 7622)
+++ roadveh_gui.c	(working copy)
@@ -42,7 +42,7 @@
 	y += 10;
 
 	/* Running cost */
-	SetDParam(0, rvi->running_cost * _price.roadveh_running >> 8);
+	SetDParam(0, rvi->running_cost * (_patches.daylength_affect_economy?_patches.day_length:1) * _price.roadveh_running >> 8);
 	DrawString(x, y, STR_PURCHASE_INFO_RUNNINGCOST, 0);
 	y += 10;
 
@@ -103,7 +103,7 @@
 
 			SetDParam(0, (v->age + 365 < v->max_age) ? STR_AGE : STR_AGE_RED);
 			SetDParam(2, v->max_age / 366);
-			SetDParam(3, RoadVehInfo(v->engine_type)->running_cost * _price.roadveh_running >> 8);
+			SetDParam(3, RoadVehInfo(v->engine_type)->running_cost * (_patches.daylength_affect_economy?_patches.day_length:1) * _price.roadveh_running >> 8);
 			DrawString(2, 15, STR_900D_AGE_RUNNING_COST_YR, 0);
 		}
 
@@ -545,3 +545,7 @@
 }
 
 
+
+
+
+
Index: saveload.c
===================================================================
--- saveload.c	(revision 7622)
+++ saveload.c	(working copy)
@@ -30,7 +30,7 @@
 #include "variables.h"
 #include <setjmp.h>
 
-const uint16 SAVEGAME_VERSION = 42;
+const uint16 SAVEGAME_VERSION = 43;
 uint16 _sl_version;       /// the major savegame version identifier
 byte   _sl_minor_version; /// the minor savegame version, DO NOT USE!
 
Index: settings.c
===================================================================
--- settings.c	(revision 7622)
+++ settings.c	(working copy)
@@ -1351,6 +1351,8 @@
 	 SDT_VAR(Patches, ending_year,      SLE_INT32,0,NC|NO,2051, MIN_YEAR, MAX_YEAR, 1, STR_CONFIG_PATCHES_ENDING_YEAR,  NULL),
 	SDT_BOOL(Patches, smooth_economy,             0, 0,  true,            STR_CONFIG_PATCHES_SMOOTH_ECONOMY,   NULL),
 	SDT_BOOL(Patches, allow_shares,               0, 0,  true,            STR_CONFIG_PATCHES_ALLOW_SHARES,     NULL),
+	SDT_CONDVAR(Patches, day_length,     SLE_UINT8, 43, SL_MAX_VERSION, 0, 0,     1,   1,   32, 1, STR_CONFIG_PATCHES_DAY_LENGTH,       NULL),
+	SDT_CONDBOOL(Patches, daylength_affect_economy, 43, SL_MAX_VERSION, 0, 0, false, STR_CONFIG_PATCHES_DAY_LENGTH_ECONOMY, NULL),
 
 	/***************************************************************************/
 	/* AI section of the GUI-configure patches window */
Index: settings_gui.c
===================================================================
--- settings_gui.c	(revision 7622)
+++ settings_gui.c	(working copy)
@@ -608,6 +608,8 @@
 	"ending_year",
 	"smooth_economy",
 	"allow_shares",
+	"day_length",
+	"daylength_affect_economy",
 };
 
 static const char *_patches_ai[] = {
Index: ship_cmd.c
===================================================================
--- ship_cmd.c	(revision 7622)
+++ ship_cmd.c	(working copy)
@@ -151,7 +151,7 @@
 
 	if (v->vehstatus & VS_STOPPED) return;
 
-	cost = ShipVehInfo(v->engine_type)->running_cost * _price.ship_running / 364;
+	cost = ShipVehInfo(v->engine_type)->running_cost * (_patches.daylength_affect_economy?_patches.day_length:1) * _price.ship_running / 364;
 	v->profit_this_year -= cost >> 8;
 
 	SET_EXPENSES_TYPE(EXPENSES_SHIP_RUN);
Index: ship_gui.c
===================================================================
--- ship_gui.c	(revision 7622)
+++ ship_gui.c	(working copy)
@@ -47,7 +47,7 @@
 	y += 10;
 
 	/* Running cost */
-	SetDParam(0, svi->running_cost * _price.ship_running >> 8);
+	SetDParam(0, svi->running_cost * (_patches.daylength_affect_economy?_patches.day_length:1) * _price.ship_running >> 8);
 	DrawString(x,y, STR_PURCHASE_INFO_RUNNINGCOST, 0);
 	y += 10;
 
@@ -102,7 +102,7 @@
 
 			SetDParam(0, (v->age + 365 < v->max_age) ? STR_AGE : STR_AGE_RED);
 			SetDParam(2, v->max_age / 366);
-			SetDParam(3, ShipVehInfo(v->engine_type)->running_cost * _price.ship_running >> 8);
+			SetDParam(3, ShipVehInfo(v->engine_type)->running_cost * (_patches.daylength_affect_economy?_patches.day_length:1) * _price.ship_running >> 8);
 			DrawString(2, 15, STR_9812_AGE_RUNNING_COST_YR, 0);
 		}
 
Index: station_gui.c
===================================================================
--- station_gui.c	(revision 7622)
+++ station_gui.c	(working copy)
@@ -254,7 +254,7 @@
 	_last_station = NULL; // used for "cache" in namesorting
 	qsort((void*)sl->sort_list, sl->list_length, sizeof(sl->sort_list[0]), _station_sorter[sl->sort_type]);
 
-	sl->resort_timer = DAY_TICKS * PERIODIC_RESORT_DAYS;
+	sl->resort_timer = (DAY_TICKS*_patches.day_length) * PERIODIC_RESORT_DAYS;
 	sl->flags &= ~SL_RESORT;
 }
 
@@ -281,7 +281,7 @@
 		sl->sort_list = NULL;
 		sl->flags = SL_REBUILD;
 		sl->sort_type = 0;
-		sl->resort_timer = DAY_TICKS * PERIODIC_RESORT_DAYS;
+		sl->resort_timer = (DAY_TICKS*_patches.day_length) * PERIODIC_RESORT_DAYS;
 		break;
 	}
 
@@ -476,7 +476,7 @@
 	case WE_TICK:
 		if (--sl->resort_timer == 0) {
 			DEBUG(misc, 3, "Periodic rebuild station list player %d", owner);
-			sl->resort_timer = DAY_TICKS * PERIODIC_RESORT_DAYS;
+			sl->resort_timer = (DAY_TICKS*_patches.day_length) * PERIODIC_RESORT_DAYS;
 			sl->flags |= VL_REBUILD;
 			SetWindowDirty(w);
 		}
Index: train_cmd.c
===================================================================
--- train_cmd.c	(revision 7622)
+++ train_cmd.c	(working copy)
@@ -3206,12 +3206,12 @@
 			v->cur_speed = 0;
 			v->subspeed = 0;
 			v->progress = 255 - 100;
-			if (++v->load_unload_time_rem < _patches.wait_oneway_signal * 20) return;
+			if (++v->load_unload_time_rem < _patches.wait_oneway_signal * 20 * _patches.day_length) return;
 		} else if (HasSignalOnTrackdir(gp.new_tile, i)){
 			v->cur_speed = 0;
 			v->subspeed = 0;
 			v->progress = 255-10;
-			if (++v->load_unload_time_rem < _patches.wait_twoway_signal * 73) {
+			if (++v->load_unload_time_rem < _patches.wait_twoway_signal * 73 * _patches.day_length) {
 				TileIndex o_tile = gp.new_tile + TileOffsByDiagDir(enterdir);
 				VehicleAtSignalData vasd;
 				vasd.tile = o_tile;
Index: variables.h
===================================================================
--- variables.h	(revision 7622)
+++ variables.h	(working copy)
@@ -216,6 +216,9 @@
 
 	uint8 freight_trains; ///< Value to multiply the weight of cargo by
 
+	uint8 day_length; //Multiplier for the length of one day
+	bool daylength_affect_economy;
+
 	/** YAPF settings */
 	YapfSettings  yapf;