diff --git a/source/glest_game/ai/path_finder.cpp b/source/glest_game/ai/path_finder.cpp
index 7002311d5..743038dc1 100644
--- a/source/glest_game/ai/path_finder.cpp
+++ b/source/glest_game/ai/path_finder.cpp
@@ -97,11 +97,10 @@ void PathFinder::clearCaches() {
 	for(int factionIndex = 0; factionIndex < GameConstants::maxPlayers; ++factionIndex) {
 		static string mutexOwnerId = string(__FILE__) + string("_") + intToStr(__LINE__);
 		FactionState &faction = factions.getFactionState(factionIndex);
-		MutexSafeWrapper safeMutex(faction.getMutex(),mutexOwnerId);
+		MutexSafeWrapper safeMutex(faction.getMutexPreCache(),mutexOwnerId);
 
 		faction.precachedTravelState.clear();
 		faction.precachedPath.clear();
-		faction.badCellList.clear();
 	}
 }
 
@@ -110,11 +109,10 @@ void PathFinder::clearUnitPrecache(Unit *unit) {
 		int factionIndex = unit->getFactionIndex();
 		static string mutexOwnerId = string(__FILE__) + string("_") + intToStr(__LINE__);
 		FactionState &faction = factions.getFactionState(factionIndex);
-		MutexSafeWrapper safeMutex(faction.getMutex(),mutexOwnerId);
+		MutexSafeWrapper safeMutex(faction.getMutexPreCache(),mutexOwnerId);
 
 		faction.precachedTravelState[unit->getId()] = tsImpossible;
 		faction.precachedPath[unit->getId()].clear();
-		faction.badCellList.clear();
 	}
 }
 
@@ -123,7 +121,7 @@ void PathFinder::removeUnitPrecache(Unit *unit) {
 		int factionIndex = unit->getFactionIndex();
 		static string mutexOwnerId = string(__FILE__) + string("_") + intToStr(__LINE__);
 		FactionState &faction = factions.getFactionState(factionIndex);
-		MutexSafeWrapper safeMutex(faction.getMutex(),mutexOwnerId);
+		MutexSafeWrapper safeMutex(faction.getMutexPreCache(),mutexOwnerId);
 
 		if(faction.precachedTravelState.find(unit->getId()) != faction.precachedTravelState.end()) {
 			faction.precachedTravelState.erase(unit->getId());
@@ -451,13 +449,14 @@ TravelState PathFinder::findPath(Unit *unit, const Vec2i &finalPos, bool *wasStu
 						int factionIndex = unit->getFactionIndex();
 						static string mutexOwnerId = string(__FILE__) + string("_") + intToStr(__LINE__);
 						FactionState &faction = factions.getFactionState(factionIndex);
-						MutexSafeWrapper safeMutex(faction.getMutex(),mutexOwnerId);
+						MutexSafeWrapper safeMutexPreCache(faction.getMutexPreCache(),mutexOwnerId);
 
 						if(faction.precachedPath[unit->getId()].size() <= 0) {
 							throw megaglest_runtime_error("factions[unit->getFactionIndex()].precachedPath[unit->getId()].size() <= 0!");
 						}
 
 						pos = faction.precachedPath[unit->getId()][0];
+						safeMutexPreCache.ReleaseLock();
 
 						codeLocation = "39";
 					}
diff --git a/source/glest_game/ai/path_finder.h b/source/glest_game/ai/path_finder.h
index 33cd3edbe..e1659320a 100644
--- a/source/glest_game/ai/path_finder.h
+++ b/source/glest_game/ai/path_finder.h
@@ -89,25 +89,37 @@ public:
 	class FactionState {
 	protected:
 		Mutex *factionMutex;
+		Mutex *factionMutexPrecache;
 	public:
-		FactionState() : factionMutex(new Mutex()) {
+		FactionState() :
+			//factionMutex(new Mutex()),
+			factionMutex(NULL),
+			factionMutexPrecache(new Mutex) {
+
 			openPosList.clear();
 			openNodesList.clear();
 			closedNodesList.clear();
 			nodePool.clear();
 			nodePoolCount = 0;
 			useMaxNodeCount = 0;
+
 			precachedTravelState.clear();
 			precachedPath.clear();
-			badCellList.clear();
 		}
 		~FactionState() {
 			delete factionMutex;
 			factionMutex = NULL;
+
+			delete factionMutexPrecache;
+			factionMutexPrecache = NULL;
 		}
 		Mutex * getMutex() {
 			return factionMutex;
 		}
+		Mutex * getMutexPreCache() {
+			return factionMutexPrecache;
+		}
+
 		std::map<Vec2i, bool> openPosList;
 		std::map<float, Nodes> openNodesList;
 		std::map<float, Nodes> closedNodesList;
@@ -119,7 +131,6 @@ public:
 
 		std::map<int,TravelState> precachedTravelState;
 		std::map<int,std::vector<Vec2i> > precachedPath;
-		std::map<int,std::map<Field,BadUnitNodeList> > badCellList;
 	};
 
 	class FactionStateManager {