diff --git a/src/BulletCollision/CollisionDispatch/btCollisionDispatcher.cpp b/src/BulletCollision/CollisionDispatch/btCollisionDispatcher.cpp
index d4c9e1476..c78ed408e 100644
--- a/src/BulletCollision/CollisionDispatch/btCollisionDispatcher.cpp
+++ b/src/BulletCollision/CollisionDispatch/btCollisionDispatcher.cpp
@@ -56,7 +56,10 @@ m_emptyCreateFunc(0)
 		}
 	}
 }
-
+//if you want to not link with the default collision algorithms, you can
+//define BT_EXCLUDE_DEFAULT_COLLISIONALGORITHM_REGISTRATION 
+//in your Bullet library build system
+#ifndef BT_EXCLUDE_DEFAULT_COLLISIONALGORITHM_REGISTRATION
 
 btCollisionDispatcher::btCollisionDispatcher (): 
 	m_useIslands(true),
@@ -86,6 +89,9 @@ btCollisionDispatcher::btCollisionDispatcher ():
 	
 };
 
+#endif //BT_EXCLUDE_DEFAULT_COLLISIONALGORITHM_REGISTRATION
+
+
 void btCollisionDispatcher::registerCollisionCreateFunc(int proxyType0, int proxyType1, btCollisionAlgorithmCreateFunc *createFunc)
 {
 	m_doubleDispatch[proxyType0][proxyType1] = createFunc;
@@ -164,6 +170,8 @@ btCollisionAlgorithm* btCollisionDispatcher::findAlgorithm(btCollisionObject* bo
 }
 
 
+#ifndef BT_EXCLUDE_DEFAULT_COLLISIONALGORITHM_REGISTRATION
+
 btCollisionAlgorithmCreateFunc* btCollisionDispatcher::internalFindCreateFunc(int proxyType0,int proxyType1)
 {
 	
@@ -197,6 +205,8 @@ btCollisionAlgorithmCreateFunc* btCollisionDispatcher::internalFindCreateFunc(in
 	return m_emptyCreateFunc;
 }
 
+#endif //BT_EXCLUDE_DEFAULT_COLLISIONALGORITHM_REGISTRATION
+
 
 #ifndef USE_DISPATCH_REGISTRY_ARRAY
 
diff --git a/src/BulletCollision/CollisionDispatch/btConvexConvexAlgorithm.cpp b/src/BulletCollision/CollisionDispatch/btConvexConvexAlgorithm.cpp
index 09457aea3..31023b9d9 100644
--- a/src/BulletCollision/CollisionDispatch/btConvexConvexAlgorithm.cpp
+++ b/src/BulletCollision/CollisionDispatch/btConvexConvexAlgorithm.cpp
@@ -43,23 +43,9 @@ subject to the following restrictions:
 #include "BulletCollision/NarrowPhaseCollision/btGjkEpaPenetrationDepthSolver.h"
 
 
-#ifdef WIN32
-#if _MSC_VER >= 1310
-//only use SIMD Hull code under Win32
-#ifdef TEST_HULL
-#define USE_HULL 1
-#endif //TEST_HULL
-#endif //_MSC_VER 
-#endif //WIN32
 
 
-#ifdef USE_HULL
 
-#include "NarrowPhaseCollision/Hull.h"
-#include "NarrowPhaseCollision/HullContactCollector.h"
-
-
-#endif //USE_HULL
 
 
 btConvexConvexAlgorithm::CreateFunc::CreateFunc()
diff --git a/src/BulletCollision/NarrowPhaseCollision/btManifoldPoint.h b/src/BulletCollision/NarrowPhaseCollision/btManifoldPoint.h
index 00a9206fe..48c5545ca 100644
--- a/src/BulletCollision/NarrowPhaseCollision/btManifoldPoint.h
+++ b/src/BulletCollision/NarrowPhaseCollision/btManifoldPoint.h
@@ -63,7 +63,7 @@ class btManifoldPoint
 			float	m_combinedRestitution;
 
 				
-			void*	m_userPersistentData;
+			mutable void*	m_userPersistentData;
 
 			int		m_lifeTime;//lifetime of the contactpoint in frames