--- a/depot.c	Tue Apr 18 18:02:52 2006 +0000
+++ b/depot.c	Tue Apr 18 18:48:50 2006 +0000
@@ -28,7 +28,7 @@
 }
 
 /* Initialize the town-pool */
-MemoryPool _depot_pool = { "Depots", DEPOT_POOL_MAX_BLOCKS, DEPOT_POOL_BLOCK_SIZE_BITS, sizeof(Depot), &DepotPoolNewBlock, 0, 0, NULL };
+MemoryPool _depot_pool = { "Depots", DEPOT_POOL_MAX_BLOCKS, DEPOT_POOL_BLOCK_SIZE_BITS, sizeof(Depot), &DepotPoolNewBlock, NULL, 0, 0, NULL };
 
 
 /**

--- a/engine.c	Tue Apr 18 18:02:52 2006 +0000
+++ b/engine.c	Tue Apr 18 18:48:50 2006 +0000
@@ -507,7 +507,7 @@
 	ENGINE_RENEW_POOL_MAX_BLOCKS      = 8000,
 };
 
-MemoryPool _engine_renew_pool = { "EngineRe", ENGINE_RENEW_POOL_MAX_BLOCKS, ENGINE_RENEW_POOL_BLOCK_SIZE_BITS, sizeof(EngineRenew), &EngineRenewPoolNewBlock, 0, 0, NULL };
+MemoryPool _engine_renew_pool = { "EngineRe", ENGINE_RENEW_POOL_MAX_BLOCKS, ENGINE_RENEW_POOL_BLOCK_SIZE_BITS, sizeof(EngineRenew), &EngineRenewPoolNewBlock, NULL, 0, 0, NULL };
 
 static inline uint16 GetEngineRenewPoolSize(void)
 {

--- a/industry_cmd.c	Tue Apr 18 18:02:52 2006 +0000
+++ b/industry_cmd.c	Tue Apr 18 18:48:50 2006 +0000
@@ -38,7 +38,7 @@
 }
 
 /* Initialize the industry-pool */
-MemoryPool _industry_pool = { "Industry", INDUSTRY_POOL_MAX_BLOCKS, INDUSTRY_POOL_BLOCK_SIZE_BITS, sizeof(Industry), &IndustryPoolNewBlock, 0, 0, NULL };
+MemoryPool _industry_pool = { "Industry", INDUSTRY_POOL_MAX_BLOCKS, INDUSTRY_POOL_BLOCK_SIZE_BITS, sizeof(Industry), &IndustryPoolNewBlock, NULL, 0, 0, NULL };
 
 static byte _industry_sound_ctr;
 static TileIndex _industry_sound_tile;

--- a/order_cmd.c	Tue Apr 18 18:02:52 2006 +0000
+++ b/order_cmd.c	Tue Apr 18 18:48:50 2006 +0000
@@ -33,7 +33,7 @@
 }
 
 /* Initialize the order-pool */
-MemoryPool _order_pool = { "Orders", ORDER_POOL_MAX_BLOCKS, ORDER_POOL_BLOCK_SIZE_BITS, sizeof(Order), &OrderPoolNewBlock, 0, 0, NULL };
+MemoryPool _order_pool = { "Orders", ORDER_POOL_MAX_BLOCKS, ORDER_POOL_BLOCK_SIZE_BITS, sizeof(Order), &OrderPoolNewBlock, NULL, 0, 0, NULL };
 
 /**
  *

--- a/pool.c	Tue Apr 18 18:02:52 2006 +0000
+++ b/pool.c	Tue Apr 18 18:48:50 2006 +0000
@@ -16,8 +16,12 @@
 	DEBUG(misc, 4)("[Pool] (%s) Cleaning pool..", pool->name);
 
 	/* Free all blocks */
-	for (i = 0; i < pool->current_blocks; i++)
+	for (i = 0; i < pool->current_blocks; i++) {
+		if (pool->clean_block_proc != NULL) {
+			pool->clean_block_proc(i * (1 << pool->block_size_bits), (i + 1) * (1 << pool->block_size_bits) - 1);
+		}
 		free(pool->blocks[i]);
+	}
 
 	/* Free the block itself */
 	free(pool->blocks);

--- a/pool.h	Tue Apr 18 18:02:52 2006 +0000
+++ b/pool.h	Tue Apr 18 18:48:50 2006 +0000
@@ -8,6 +8,8 @@
 /* The function that is called after a new block is added
      start_item is the first item of the new made block */
 typedef void MemoryPoolNewBlock(uint start_item);
+/* The function that is called before a block is cleaned up */
+typedef void MemoryPoolCleanBlock(uint start_item, uint end_item);
 
 /**
  * Stuff for dynamic vehicles. Use the wrappers to access the MemoryPool
@@ -22,6 +24,8 @@
 
 	/// Pointer to a function that is called after a new block is added
 	MemoryPoolNewBlock *new_block_proc;
+	/// Pointer to a function that is called to clean a block
+	MemoryPoolCleanBlock *clean_block_proc;
 
 	uint current_blocks;        ///< How many blocks we have in our pool
 	uint total_items;           ///< How many items we now have in this pool

--- a/saveload.c	Tue Apr 18 18:02:52 2006 +0000
+++ b/saveload.c	Tue Apr 18 18:48:50 2006 +0000
@@ -1021,7 +1021,7 @@
 } ThreadedSave;
 
 /* A maximum size of of 128K * 500 = 64.000KB savegames */
-static MemoryPool _save_pool = {"Savegame", SAVE_POOL_MAX_BLOCKS, SAVE_POOL_BLOCK_SIZE_BITS, sizeof(byte), NULL, 0, 0, NULL};
+static MemoryPool _save_pool = {"Savegame", SAVE_POOL_MAX_BLOCKS, SAVE_POOL_BLOCK_SIZE_BITS, sizeof(byte), NULL, NULL, 0, 0, NULL};
 static ThreadedSave _ts;
 
 static bool InitMem(void)

--- a/signs.c	Tue Apr 18 18:02:52 2006 +0000
+++ b/signs.c	Tue Apr 18 18:48:50 2006 +0000
@@ -30,7 +30,7 @@
 }
 
 /* Initialize the sign-pool */
-MemoryPool _sign_pool = { "Signs", SIGN_POOL_MAX_BLOCKS, SIGN_POOL_BLOCK_SIZE_BITS, sizeof(SignStruct), &SignPoolNewBlock, 0, 0, NULL };
+MemoryPool _sign_pool = { "Signs", SIGN_POOL_MAX_BLOCKS, SIGN_POOL_BLOCK_SIZE_BITS, sizeof(SignStruct), &SignPoolNewBlock, NULL, 0, 0, NULL };
 
 /**
  *

--- a/station_cmd.c	Tue Apr 18 18:02:52 2006 +0000
+++ b/station_cmd.c	Tue Apr 18 18:48:50 2006 +0000
@@ -61,8 +61,8 @@
 }
 
 /* Initialize the station-pool and roadstop-pool */
-MemoryPool _station_pool = { "Stations", STATION_POOL_MAX_BLOCKS, STATION_POOL_BLOCK_SIZE_BITS, sizeof(Station), &StationPoolNewBlock, 0, 0, NULL };
-MemoryPool _roadstop_pool = { "RoadStop", ROADSTOP_POOL_MAX_BLOCKS, ROADSTOP_POOL_BLOCK_SIZE_BITS, sizeof(RoadStop), &RoadStopPoolNewBlock, 0, 0, NULL };
+MemoryPool _station_pool = { "Stations", STATION_POOL_MAX_BLOCKS, STATION_POOL_BLOCK_SIZE_BITS, sizeof(Station), &StationPoolNewBlock, NULL, 0, 0, NULL };
+MemoryPool _roadstop_pool = { "RoadStop", ROADSTOP_POOL_MAX_BLOCKS, ROADSTOP_POOL_BLOCK_SIZE_BITS, sizeof(RoadStop), &RoadStopPoolNewBlock, NULL, 0, 0, NULL };
 
 
 // FIXME -- need to be embedded into Airport variable. Is dynamically

--- a/town_cmd.c	Tue Apr 18 18:02:52 2006 +0000
+++ b/town_cmd.c	Tue Apr 18 18:48:50 2006 +0000
@@ -45,7 +45,7 @@
 }
 
 /* Initialize the town-pool */
-MemoryPool _town_pool = { "Towns", TOWN_POOL_MAX_BLOCKS, TOWN_POOL_BLOCK_SIZE_BITS, sizeof(Town), &TownPoolNewBlock, 0, 0, NULL };
+MemoryPool _town_pool = { "Towns", TOWN_POOL_MAX_BLOCKS, TOWN_POOL_BLOCK_SIZE_BITS, sizeof(Town), &TownPoolNewBlock, NULL, 0, 0, NULL };
 
 // Local
 static int _grow_town_result;

--- a/vehicle.c	Tue Apr 18 18:02:52 2006 +0000
+++ b/vehicle.c	Tue Apr 18 18:48:50 2006 +0000
@@ -80,7 +80,7 @@
 }
 
 /* Initialize the vehicle-pool */
-MemoryPool _vehicle_pool = { "Vehicle", VEHICLES_POOL_MAX_BLOCKS, VEHICLES_POOL_BLOCK_SIZE_BITS, sizeof(Vehicle), &VehiclePoolNewBlock, 0, 0, NULL };
+MemoryPool _vehicle_pool = { "Vehicle", VEHICLES_POOL_MAX_BLOCKS, VEHICLES_POOL_BLOCK_SIZE_BITS, sizeof(Vehicle), &VehiclePoolNewBlock, NULL, 0, 0, NULL };
 
 void VehicleServiceInDepot(Vehicle *v)
 {

--- a/waypoint.c	Tue Apr 18 18:02:52 2006 +0000
+++ b/waypoint.c	Tue Apr 18 18:48:50 2006 +0000
@@ -39,7 +39,7 @@
 }
 
 /* Initialize the town-pool */
-MemoryPool _waypoint_pool = { "Waypoints", WAYPOINT_POOL_MAX_BLOCKS, WAYPOINT_POOL_BLOCK_SIZE_BITS, sizeof(Waypoint), &WaypointPoolNewBlock, 0, 0, NULL };
+MemoryPool _waypoint_pool = { "Waypoints", WAYPOINT_POOL_MAX_BLOCKS, WAYPOINT_POOL_BLOCK_SIZE_BITS, sizeof(Waypoint), &WaypointPoolNewBlock, NULL, 0, 0, NULL };
 
 /* Create a new waypoint */
 static Waypoint* AllocateWaypoint(void)