diff --git a/src/BulletCollision/CMakeLists.txt b/src/BulletCollision/CMakeLists.txt
index f5058aeac..cef6293e2 100644
--- a/src/BulletCollision/CMakeLists.txt
+++ b/src/BulletCollision/CMakeLists.txt
@@ -46,6 +46,7 @@ SET(BulletCollision_SRCS
 	CollisionShapes/btConvexHullShape.cpp
 	CollisionShapes/btConvexInternalShape.cpp
 	CollisionShapes/btConvexPointCloudShape.cpp
+	CollisionShapes/btConvexPolyhedron.cpp
 	CollisionShapes/btConvexShape.cpp
 	CollisionShapes/btConvex2dShape.cpp
 	CollisionShapes/btConvexTriangleMeshShape.cpp
@@ -92,6 +93,7 @@ SET(BulletCollision_SRCS
 	NarrowPhaseCollision/btRaycastCallback.cpp
 	NarrowPhaseCollision/btSubSimplexConvexCast.cpp
 	NarrowPhaseCollision/btVoronoiSimplexSolver.cpp
+	NarrowPhaseCollision/btPolyhedralContactClipping.cpp
 )
 
 SET(Root_HDRS
@@ -150,6 +152,7 @@ SET(CollisionShapes_HDRS
 	CollisionShapes/btConvexHullShape.h
 	CollisionShapes/btConvexInternalShape.h
 	CollisionShapes/btConvexPointCloudShape.h
+	CollisionShapes/btConvexPolyhedron.h
 	CollisionShapes/btConvexShape.h
 	CollisionShapes/btConvex2dShape.h
 	CollisionShapes/btConvexTriangleMeshShape.h
@@ -224,6 +227,7 @@ SET(NarrowPhaseCollision_HDRS
 	NarrowPhaseCollision/btSimplexSolverInterface.h
 	NarrowPhaseCollision/btSubSimplexConvexCast.h
 	NarrowPhaseCollision/btVoronoiSimplexSolver.h
+	NarrowPhaseCollision/btPolyhedralContactClipping.h
 )
 
 SET(BulletCollision_HDRS
diff --git a/src/BulletCollision/CollisionDispatch/btConvexConvexAlgorithm.cpp b/src/BulletCollision/CollisionDispatch/btConvexConvexAlgorithm.cpp
index ede1afb2a..302bfe0a2 100644
--- a/src/BulletCollision/CollisionDispatch/btConvexConvexAlgorithm.cpp
+++ b/src/BulletCollision/CollisionDispatch/btConvexConvexAlgorithm.cpp
@@ -48,7 +48,7 @@ subject to the following restrictions:
 
 #include "BulletCollision/NarrowPhaseCollision/btGjkEpa2.h"
 #include "BulletCollision/NarrowPhaseCollision/btGjkEpaPenetrationDepthSolver.h"
-
+#include "BulletCollision/NarrowPhaseCollision/btPolyhedralContactClipping.h"
 
 
 ///////////
@@ -330,7 +330,6 @@ void btConvexConvexAlgorithm ::processCollision (btCollisionObject* body0,btColl
 	}
 #endif //BT_DISABLE_CAPSULE_CAPSULE_COLLIDER
 
-
 #ifdef USE_SEPDISTANCE_UTIL2
 	if (dispatchInfo.m_useConvexConservativeDistanceUtil)
 	{
@@ -389,6 +388,54 @@ void btConvexConvexAlgorithm ::processCollision (btCollisionObject* body0,btColl
 	}
 #endif //USE_SEPDISTANCE_UTIL2
 
+
+	if (min0->isPolyhedral() && min1->isPolyhedral())
+	{
+		btPolyhedralConvexShape* polyhedronA = (btPolyhedralConvexShape*) min0;
+		btPolyhedralConvexShape* polyhedronB = (btPolyhedralConvexShape*) min1;
+		if (polyhedronA->getConvexPolyhedron() && polyhedronB->getConvexPolyhedron())
+		{
+		
+			btScalar maxDist = 0.f;
+
+			if (dispatchInfo.m_convexMaxDistanceUseCPT)
+			{
+				maxDist = min0->getMargin() + min1->getMargin() + m_manifoldPtr->getContactProcessingThreshold();
+			} else
+			{
+				maxDist = min0->getMargin() + min1->getMargin() + m_manifoldPtr->getContactBreakingThreshold();
+			}
+
+			maxDist =0.f;
+			btVector3 sepNormalWorldSpace;
+//#define USE_SAT_TEST
+#ifdef USE_SAT_TEST
+			bool foundSepAxis = btPolyhedralContactClipping::findSeparatingAxis(
+				*polyhedronA->getConvexPolyhedron(), *polyhedronB->getConvexPolyhedron(),
+				body0->getWorldTransform(), 
+				body1->getWorldTransform(),
+				sepNormalWorldSpace);
+#else
+			bool foundSepAxis  = true;
+			sepNormalWorldSpace = gjkPairDetector.getCachedSeparatingAxis().normalized();
+#endif //USE_SAT_TEST
+			if (foundSepAxis)
+			{
+				btPolyhedralContactClipping::clipFaceContacts(sepNormalWorldSpace, *polyhedronA->getConvexPolyhedron(), *polyhedronB->getConvexPolyhedron(),
+					body0->getWorldTransform(), 
+					body1->getWorldTransform(), maxDist, *resultOut);
+
+				if (m_ownManifold)
+				{
+					resultOut->refreshContactPoints();
+				}
+				return;
+			}
+
+
+		}
+	}
+
 	//now perform 'm_numPerturbationIterations' collision queries with the perturbated collision objects
 	
 	//perform perturbation when more then 'm_minimumPointsPerturbationThreshold' points
diff --git a/src/BulletCollision/CollisionShapes/btBoxShape.h b/src/BulletCollision/CollisionShapes/btBoxShape.h
index b405efc8e..06ed7a739 100644
--- a/src/BulletCollision/CollisionShapes/btBoxShape.h
+++ b/src/BulletCollision/CollisionShapes/btBoxShape.h
@@ -145,7 +145,7 @@ public:
 
 	virtual void getVertex(int i,btVector3& vtx) const
 	{
-		btVector3 halfExtents = getHalfExtentsWithoutMargin();
+		btVector3 halfExtents = getHalfExtentsWithMargin();
 
 		vtx = btVector3(
 				halfExtents.x() * (1-(i&1)) - halfExtents.x() * (i&1),
diff --git a/src/BulletCollision/CollisionShapes/btConvexPolyhedron.cpp b/src/BulletCollision/CollisionShapes/btConvexPolyhedron.cpp
new file mode 100644
index 000000000..6fceb6f25
--- /dev/null
+++ b/src/BulletCollision/CollisionShapes/btConvexPolyhedron.cpp
@@ -0,0 +1,185 @@
+/*
+Bullet Continuous Collision Detection and Physics Library
+Copyright (c) 2011 Advanced Micro Devices, Inc.  http://bulletphysics.org
+
+This software is provided 'as-is', without any express or implied warranty.
+In no event will the authors be held liable for any damages arising from the use of this software.
+Permission is granted to anyone to use this software for any purpose, 
+including commercial applications, and to alter it and redistribute it freely, 
+subject to the following restrictions:
+
+1. The origin of this software must not be misrepresented; you must not claim that you wrote the original software. If you use this software in a product, an acknowledgment in the product documentation would be appreciated but is not required.
+2. Altered source versions must be plainly marked as such, and must not be misrepresented as being the original software.
+3. This notice may not be removed or altered from any source distribution.
+*/
+
+
+///This file was written by Erwin Coumans
+///Separating axis rest based on work from Pierre Terdiman, see
+///And contact clipping based on work from Simon Hobbs
+
+
+#include "btConvexPolyhedron.h"
+#include "LinearMath/btHashMap.h"
+
+btConvexPolyhedron::btConvexPolyhedron()
+{
+
+}
+btConvexPolyhedron::~btConvexPolyhedron()
+{
+
+}
+
+
+inline bool IsAlmostZero(const btVector3& v)
+{
+	if(fabsf(v.x())>1e-6 || fabsf(v.y())>1e-6 || fabsf(v.z())>1e-6)	return false;
+	return true;
+}
+
+struct btInternalVertexPair
+{
+	btInternalVertexPair(short int v0,short int v1)
+		:m_v0(v0),
+		m_v1(v1)
+	{
+		if (m_v1>m_v0)
+			btSwap(m_v0,m_v1);
+	}
+	short int m_v0;
+	short int m_v1;
+	int getHash() const
+	{
+		return m_v0+(m_v1<<16);
+	}
+	bool equals(const btInternalVertexPair& other) const
+	{
+		return m_v0==other.m_v0 && m_v1==other.m_v1;
+	}
+};
+
+struct btInternalEdge
+{
+	btInternalEdge()
+		:m_face0(-1),
+		m_face1(-1)
+	{
+	}
+	short int m_face0;
+	short int m_face1;
+};
+
+//
+
+void	btConvexPolyhedron::initialize()
+{
+	btHashMap<btInternalVertexPair,btInternalEdge> edges;
+
+	float TotalArea = 0.0f;
+	
+	m_localCenter.setValue(0, 0, 0);
+	for(int i=0;i<m_faces.size();i++)
+	{
+		int numVertices = m_faces[i].m_indices.size();
+		int NbTris = numVertices;
+		for(int j=0;j<NbTris;j++)
+		{
+			int k = (j+1)%numVertices;
+			btInternalVertexPair vp(m_faces[i].m_indices[j],m_faces[i].m_indices[k]);
+			btInternalEdge* edptr = edges.find(vp);
+			btVector3 edge = m_vertices[vp.m_v1]-m_vertices[vp.m_v0];
+			edge.normalize();
+
+			bool found = false;
+
+			for (int p=0;p<m_uniqueEdges.size();p++)
+			{
+				
+				if (IsAlmostZero(m_uniqueEdges[p]-edge) || 
+					IsAlmostZero(m_uniqueEdges[p]+edge))
+				{
+					found = true;
+					break;
+				}
+			}
+
+			if (!found)
+			{
+				m_uniqueEdges.push_back(edge);
+			}
+
+			if (edptr)
+			{
+				btAssert(edptr->m_face0>=0);
+				btAssert(edptr->m_face1<0);
+				edptr->m_face1 = i;
+			} else
+			{
+				btInternalEdge ed;
+				ed.m_face0 = i;
+				edges.insert(vp,ed);
+			}
+		}
+	}
+
+	for(int i=0;i<m_faces.size();i++)
+	{
+		int numVertices = m_faces[i].m_indices.size();
+		m_faces[i].m_connectedFaces.resize(numVertices);
+
+		for(int j=0;j<numVertices;j++)
+		{
+			int k = (j+1)%numVertices;
+			btInternalVertexPair vp(m_faces[i].m_indices[j],m_faces[i].m_indices[k]);
+			btInternalEdge* edptr = edges.find(vp);
+			btAssert(edptr);
+			btAssert(edptr->m_face0>=0);
+			btAssert(edptr->m_face1>=0);
+
+			int connectedFace = (edptr->m_face0==i)?edptr->m_face1:edptr->m_face0;
+			m_faces[i].m_connectedFaces[j] = connectedFace;
+		}
+	}
+
+	for(int i=0;i<m_faces.size();i++)
+	{
+		int numVertices = m_faces[i].m_indices.size();
+		int NbTris = numVertices-2;
+		
+		const btVector3& p0 = m_vertices[m_faces[i].m_indices[0]];
+		for(int j=1;j<=NbTris;j++)
+		{
+			int k = (j+1)%numVertices;
+			const btVector3& p1 = m_vertices[m_faces[i].m_indices[j]];
+			const btVector3& p2 = m_vertices[m_faces[i].m_indices[k]];
+			float Area = ((p0 - p1).cross(p0 - p2)).length() * 0.5f;
+			btVector3 Center = (p0+p1+p2)/3.0f;
+			m_localCenter += Area * Center;
+			TotalArea += Area;
+		}
+	}
+	m_localCenter /= TotalArea;
+
+}
+
+
+void btConvexPolyhedron::project(const btTransform& trans, const btVector3& dir, float& min, float& max) const
+{
+	min = FLT_MAX;
+	max = -FLT_MAX;
+	int numVerts = m_vertices.size();
+	for(int i=0;i<numVerts;i++)
+	{
+		btVector3 pt = trans * m_vertices[i];
+		float dp = pt.dot(dir);
+		if(dp < min)	min = dp;
+		if(dp > max)	max = dp;
+	}
+	if(min>max)
+	{
+		float tmp = min;
+		min = max;
+		max = tmp;
+	}
+}
\ No newline at end of file
diff --git a/src/BulletCollision/CollisionShapes/btConvexPolyhedron.h b/src/BulletCollision/CollisionShapes/btConvexPolyhedron.h
new file mode 100644
index 000000000..a64cdbfd7
--- /dev/null
+++ b/src/BulletCollision/CollisionShapes/btConvexPolyhedron.h
@@ -0,0 +1,54 @@
+/*
+Bullet Continuous Collision Detection and Physics Library
+Copyright (c) 2011 Advanced Micro Devices, Inc.  http://bulletphysics.org
+
+This software is provided 'as-is', without any express or implied warranty.
+In no event will the authors be held liable for any damages arising from the use of this software.
+Permission is granted to anyone to use this software for any purpose, 
+including commercial applications, and to alter it and redistribute it freely, 
+subject to the following restrictions:
+
+1. The origin of this software must not be misrepresented; you must not claim that you wrote the original software. If you use this software in a product, an acknowledgment in the product documentation would be appreciated but is not required.
+2. Altered source versions must be plainly marked as such, and must not be misrepresented as being the original software.
+3. This notice may not be removed or altered from any source distribution.
+*/
+
+
+///This file was written by Erwin Coumans
+
+
+#ifndef _BT_POLYHEDRAL_FEATURES_H
+#define _BT_POLYHEDRAL_FEATURES_H
+
+#include "LinearMath/btTransform.h"
+#include "LinearMath/btAlignedObjectArray.h"
+
+
+struct btFace
+{
+	btAlignedObjectArray<int>	m_indices;
+	btAlignedObjectArray<int>	m_connectedFaces;
+	float	m_plane[4];
+};
+
+
+class btConvexPolyhedron
+{
+	public:
+	btConvexPolyhedron();
+	virtual	~btConvexPolyhedron();
+
+	btAlignedObjectArray<btVector3>	m_vertices;
+	btAlignedObjectArray<btFace>	m_faces;
+	btAlignedObjectArray<btVector3> m_uniqueEdges;
+	btVector3		m_localCenter;
+
+	void	initialize();
+
+	void project(const btTransform& trans, const btVector3& dir, float& min, float& max) const;
+};
+
+	
+#endif //_BT_POLYHEDRAL_FEATURES_H
+
+
diff --git a/src/BulletCollision/CollisionShapes/btPolyhedralConvexShape.cpp b/src/BulletCollision/CollisionShapes/btPolyhedralConvexShape.cpp
index b1ecb3e43..6ddb7ad83 100644
--- a/src/BulletCollision/CollisionShapes/btPolyhedralConvexShape.cpp
+++ b/src/BulletCollision/CollisionShapes/btPolyhedralConvexShape.cpp
@@ -14,12 +14,140 @@ subject to the following restrictions:
 */
 
 #include "BulletCollision/CollisionShapes/btPolyhedralConvexShape.h"
+#include "btConvexPolyhedron.h"
+#include "LinearMath/btConvexHullComputer.h"
+#include <new.h>
 
-btPolyhedralConvexShape::btPolyhedralConvexShape() :btConvexInternalShape()
+btPolyhedralConvexShape::btPolyhedralConvexShape() :btConvexInternalShape(),
+m_polyhedron(0)
 {
 
 }
 
+btPolyhedralConvexShape::~btPolyhedralConvexShape()
+{
+	if (m_polyhedron)
+	{
+		btAlignedFree(m_polyhedron);
+	}
+}
+
+bool	btPolyhedralConvexShape::initializePolyhedralFeatures()
+{
+	if (m_polyhedron)
+		btAlignedFree(m_polyhedron);
+	
+	void* mem = btAlignedAlloc(sizeof(btConvexPolyhedron),16);
+	m_polyhedron = new (mem) btConvexPolyhedron;
+
+	btAlignedObjectArray<btVector3> tmpVertices;
+	for (int i=0;i<getNumVertices();i++)
+	{
+		btVector3& newVertex = tmpVertices.expand();
+		getVertex(i,newVertex);
+	}
+
+	btConvexHullComputer conv;
+	conv.compute(&tmpVertices[0].getX(), sizeof(btVector3),tmpVertices.size(),0.f,0.f);
+
+	btAlignedObjectArray<btVector3> faceNormals;
+	int numFaces = conv.faces.size();
+	faceNormals.resize(numFaces);
+	btConvexHullComputer* convexUtil = &conv;
+
+	
+	
+	m_polyhedron->m_faces.resize(numFaces);
+	int numVertices = convexUtil->vertices.size();
+	m_polyhedron->m_vertices.resize(numVertices);
+	for (int p=0;p<numVertices;p++)
+	{
+		m_polyhedron->m_vertices[p] = convexUtil->vertices[p];
+	}
+
+	for (int i=0;i<numFaces;i++)
+	{
+		int face = convexUtil->faces[i];
+		//printf("face=%d\n",face);
+		const btConvexHullComputer::Edge*  firstEdge = &convexUtil->edges[face];
+		const btConvexHullComputer::Edge*  edge = firstEdge;
+
+		btVector3 edges[3];
+		int numEdges = 0;
+		//compute face normals
+
+		btScalar maxCross2 = 0.f;
+		int chosenEdge = -1;
+
+		do
+		{
+			
+			int src = edge->getSourceVertex();
+			m_polyhedron->m_faces[i].m_indices.push_back(src);
+			int targ = edge->getTargetVertex();
+			btVector3 wa = convexUtil->vertices[src];
+
+			btVector3 wb = convexUtil->vertices[targ];
+			btVector3 newEdge = wb-wa;
+			if (!newEdge.fuzzyZero())
+			{
+				newEdge.normalize();
+				if (!numEdges)
+				{
+					edges[numEdges++] = newEdge;
+				} else
+				{
+					btVector3 cr = (edges[0].cross(newEdge));
+					btScalar cr2 = cr.length2();
+					if (cr2 > maxCross2)
+					{
+						chosenEdge = m_polyhedron->m_faces[i].m_indices.size();
+						numEdges=1;//replace current edge
+						edges[numEdges++] = newEdge;
+						maxCross2=cr2;
+					}
+				}
+			}
+
+			edge = edge->getNextEdgeOfFace();
+		} while (edge!=firstEdge);
+
+		btScalar planeEq = 1e30f;
+
+		
+		if (numEdges==2)
+		{
+			faceNormals[i] = edges[0].cross(edges[1]);
+			faceNormals[i].normalize();
+			m_polyhedron->m_faces[i].m_plane[0] = -faceNormals[i].getX();
+			m_polyhedron->m_faces[i].m_plane[1] = -faceNormals[i].getY();
+			m_polyhedron->m_faces[i].m_plane[2] = -faceNormals[i].getZ();
+			m_polyhedron->m_faces[i].m_plane[3] = planeEq;
+
+		}
+		else
+		{
+			btAssert(0);//degenerate?
+			faceNormals[i].setZero();
+		}
+
+		for (int v=0;v<m_polyhedron->m_faces[i].m_indices.size();v++)
+		{
+			btScalar eq = m_polyhedron->m_vertices[m_polyhedron->m_faces[i].m_indices[v]].dot(faceNormals[i]);
+			if (planeEq>eq)
+			{
+				planeEq=eq;
+			}
+		}
+		m_polyhedron->m_faces[i].m_plane[3] = planeEq;
+	}
+
+
+	m_polyhedron->initialize();
+
+	return true;
+}
+
 
 btVector3	btPolyhedralConvexShape::localGetSupportingVertexWithoutMargin(const btVector3& vec0)const
 {
@@ -191,3 +319,6 @@ void	btPolyhedralConvexAabbCachingShape::recalcLocalAabb()
 	#endif
 }
 
+
+
+
diff --git a/src/BulletCollision/CollisionShapes/btPolyhedralConvexShape.h b/src/BulletCollision/CollisionShapes/btPolyhedralConvexShape.h
index 2c691b956..487e9ac17 100644
--- a/src/BulletCollision/CollisionShapes/btPolyhedralConvexShape.h
+++ b/src/BulletCollision/CollisionShapes/btPolyhedralConvexShape.h
@@ -18,18 +18,32 @@ subject to the following restrictions:
 
 #include "LinearMath/btMatrix3x3.h"
 #include "btConvexInternalShape.h"
+class btConvexPolyhedron;
 
 
 ///The btPolyhedralConvexShape is an internal interface class for polyhedral convex shapes.
 class btPolyhedralConvexShape : public btConvexInternalShape
 {
+	
 
 protected:
 	
+	btConvexPolyhedron* m_polyhedron;
+
 public:
 
 	btPolyhedralConvexShape();
 
+	virtual ~btPolyhedralConvexShape();
+
+	///optional method mainly used to generate multiple contact points by clipping polyhedral features (faces/edges)
+	virtual bool	initializePolyhedralFeatures();
+
+	const btConvexPolyhedron*	getConvexPolyhedron() const
+	{
+		return m_polyhedron;
+	}
+
 	//brute force implementations
 
 	virtual btVector3	localGetSupportingVertexWithoutMargin(const btVector3& vec)const;
diff --git a/src/BulletCollision/NarrowPhaseCollision/btGjkPairDetector.cpp b/src/BulletCollision/NarrowPhaseCollision/btGjkPairDetector.cpp
index 1a5619573..8af16b9cf 100644
--- a/src/BulletCollision/NarrowPhaseCollision/btGjkPairDetector.cpp
+++ b/src/BulletCollision/NarrowPhaseCollision/btGjkPairDetector.cpp
@@ -254,20 +254,21 @@ void btGjkPairDetector::getClosestPointsNonVirtual(const ClosestPointInput& inpu
 			}
 #endif //
 			
-			m_cachedSeparatingAxis = newCachedSeparatingAxis;
 
 			//redundant m_simplexSolver->compute_points(pointOnA, pointOnB);
 
 			//are we getting any closer ?
 			if (previousSquaredDistance - squaredDistance <= SIMD_EPSILON * previousSquaredDistance) 
 			{ 
-				m_simplexSolver->backup_closest(m_cachedSeparatingAxis);
+//				m_simplexSolver->backup_closest(m_cachedSeparatingAxis);
 				checkSimplex = true;
 				m_degenerateSimplex = 12;
 				
 				break;
 			}
 
+			m_cachedSeparatingAxis = newCachedSeparatingAxis;
+
 			  //degeneracy, this is typically due to invalid/uninitialized worldtransforms for a btCollisionObject   
               if (m_curIter++ > gGjkMaxIter)   
               {   
@@ -294,7 +295,7 @@ void btGjkPairDetector::getClosestPointsNonVirtual(const ClosestPointInput& inpu
 			if (!check)
 			{
 				//do we need this backup_closest here ?
-				m_simplexSolver->backup_closest(m_cachedSeparatingAxis);
+//				m_simplexSolver->backup_closest(m_cachedSeparatingAxis);
 				m_degenerateSimplex = 13;
 				break;
 			}
@@ -303,7 +304,7 @@ void btGjkPairDetector::getClosestPointsNonVirtual(const ClosestPointInput& inpu
 		if (checkSimplex)
 		{
 			m_simplexSolver->compute_points(pointOnA, pointOnB);
-			normalInB = pointOnA-pointOnB;
+			normalInB = m_cachedSeparatingAxis;
 			btScalar lenSqr =m_cachedSeparatingAxis.length2();
 			
 			//valid normal
diff --git a/src/BulletCollision/NarrowPhaseCollision/btPolyhedralContactClipping.cpp b/src/BulletCollision/NarrowPhaseCollision/btPolyhedralContactClipping.cpp
new file mode 100644
index 000000000..ea3d185a5
--- /dev/null
+++ b/src/BulletCollision/NarrowPhaseCollision/btPolyhedralContactClipping.cpp
@@ -0,0 +1,337 @@
+/*
+Bullet Continuous Collision Detection and Physics Library
+Copyright (c) 2011 Advanced Micro Devices, Inc.  http://bulletphysics.org
+
+This software is provided 'as-is', without any express or implied warranty.
+In no event will the authors be held liable for any damages arising from the use of this software.
+Permission is granted to anyone to use this software for any purpose, 
+including commercial applications, and to alter it and redistribute it freely, 
+subject to the following restrictions:
+
+1. The origin of this software must not be misrepresented; you must not claim that you wrote the original software. If you use this software in a product, an acknowledgment in the product documentation would be appreciated but is not required.
+2. Altered source versions must be plainly marked as such, and must not be misrepresented as being the original software.
+3. This notice may not be removed or altered from any source distribution.
+*/
+
+
+///This file was written by Erwin Coumans
+///Separating axis rest based on work from Pierre Terdiman, see
+///And contact clipping based on work from Simon Hobbs
+
+
+#include "btPolyhedralContactClipping.h"
+#include "BulletCollision/CollisionShapes/btConvexPolyhedron.h"
+
+#include <float.h> //for FLT_MAX
+
+
+// Clips a face to the back of a plane
+void btPolyhedralContactClipping::clipFace(const btVertexArray& pVtxIn, btVertexArray& ppVtxOut, const btVector3& planeNormalWS,btScalar planeEqWS)
+{
+	
+	int ve;
+	btScalar ds, de;
+	int numVerts = pVtxIn.size();
+	if (numVerts < 2)
+		return;
+
+	btVector3 firstVertex=pVtxIn[pVtxIn.size()-1];
+	btVector3 endVertex = pVtxIn[0];
+	
+	ds = planeNormalWS.dot(firstVertex)+planeEqWS;
+
+	for (ve = 0; ve < numVerts; ve++)
+	{
+		endVertex=pVtxIn[ve];
+
+		de = planeNormalWS.dot(endVertex)+planeEqWS;
+
+		if (ds<0)
+		{
+			if (de<0)
+			{
+				// Start < 0, end < 0, so output endVertex
+				ppVtxOut.push_back(endVertex);
+			}
+			else
+			{
+				// Start < 0, end >= 0, so output intersection
+				ppVtxOut.push_back( 	firstVertex.lerp(endVertex,btScalar(ds * 1.f/(ds - de))));
+			}
+		}
+		else
+		{
+			if (de<0)
+			{
+				// Start >= 0, end < 0 so output intersection and end
+				ppVtxOut.push_back(firstVertex.lerp(endVertex,btScalar(ds * 1.f/(ds - de))));
+				ppVtxOut.push_back(endVertex);
+			}
+		}
+		firstVertex = endVertex;
+		ds = de;
+	}
+}
+#include <stdio.h>
+
+
+static bool TestSepAxis(const btConvexPolyhedron& hullA, const btConvexPolyhedron& hullB, const btTransform& transA,const btTransform& transB, const btVector3& sep_axis, float& depth)
+{
+	float Min0,Max0;
+	float Min1,Max1;
+	hullA.project(transA,sep_axis, Min0, Max0);
+	hullB.project(transB, sep_axis, Min1, Max1);
+
+	if(Max0<Min1 || Max1<Min0)
+		return false;
+
+	float d0 = Max0 - Min1;
+	assert(d0>=0.0f);
+	float d1 = Max1 - Min0;
+	assert(d1>=0.0f);
+	depth = d0<d1 ? d0:d1;
+	return true;
+}
+
+
+
+static int gActualSATPairTests=0;
+
+inline bool IsAlmostZero(const btVector3& v)
+{
+	if(fabsf(v.x())>1e-6 || fabsf(v.y())>1e-6 || fabsf(v.z())>1e-6)	return false;
+	return true;
+}
+
+
+bool btPolyhedralContactClipping::findSeparatingAxis(	const btConvexPolyhedron& hullA, const btConvexPolyhedron& hullB, const btTransform& transA,const btTransform& transB, btVector3& sep)
+{
+	gActualSATPairTests++;
+
+#ifdef TEST_INTERNAL_OBJECTS
+	const btVector3 c0 = transA * hullA.mLocalCenter;
+	const btVector3 c1 = transB * hullB.mLocalCenter;
+	const btVector3 DeltaC2 = c0 - c1;
+#endif
+
+	float dmin = FLT_MAX;
+	int curPlaneTests=0;
+
+	int numFacesA = hullA.m_faces.size();
+	// Test normals from hullA
+	for(int i=0;i<numFacesA;i++)
+	{
+		const btVector3 Normal(hullA.m_faces[i].m_plane[0], hullA.m_faces[i].m_plane[1], hullA.m_faces[i].m_plane[2]);
+		const btVector3 faceANormalWS = transA.getBasis() * Normal;
+
+		curPlaneTests++;
+#ifdef TEST_INTERNAL_OBJECTS
+		gExpectedNbTests++;
+		if(gUseInternalObject && !TestInternalObjects(transA,transB,DeltaC2, faceANormalWS, hullA, hullB, dmin))
+			continue;
+		gActualNbTests++;
+#endif
+
+		float d;
+		if(!TestSepAxis( hullA, hullB, transA,transB, faceANormalWS, d))
+			return false;
+
+		if(d<dmin)
+		{
+			dmin = d;
+			sep = faceANormalWS;
+		}
+	}
+
+	int numFacesB = hullB.m_faces.size();
+	// Test normals from hullB
+	for(int i=0;i<numFacesB;i++)
+	{
+		const btVector3 Normal(hullB.m_faces[i].m_plane[0], hullB.m_faces[i].m_plane[1], hullB.m_faces[i].m_plane[2]);
+		const btVector3 WorldNormal = transB.getBasis() * Normal;
+
+		curPlaneTests++;
+#ifdef TEST_INTERNAL_OBJECTS
+		gExpectedNbTests++;
+		if(gUseInternalObject && !TestInternalObjects(transA,transB,DeltaC2, WorldNormal, hullA, hullB, dmin))
+			continue;
+		gActualNbTests++;
+#endif
+
+		float d;
+		if(!TestSepAxis(hullA, hullB,transA,transB, WorldNormal,d))
+			return false;
+
+		if(d<dmin)
+		{
+			dmin = d;
+			sep = WorldNormal;
+		}
+	}
+
+	btVector3 edgeAstart,edgeAend,edgeBstart,edgeBend;
+
+	int curEdgeEdge = 0;
+	// Test edges
+	for(int e0=0;e0<hullA.m_uniqueEdges.size();e0++)
+	{
+		const btVector3 edge0 = hullA.m_uniqueEdges[e0];
+		const btVector3 WorldEdge0 = transA.getBasis() * edge0;
+		for(int e1=0;e1<hullB.m_uniqueEdges.size();e1++)
+		{
+			const btVector3 edge1 = hullB.m_uniqueEdges[e1];
+			const btVector3 WorldEdge1 = transB.getBasis() * edge1;
+
+			btVector3 Cross = WorldEdge0.cross(WorldEdge1);
+			curEdgeEdge++;
+			if(!IsAlmostZero(Cross))
+			{
+				Cross = Cross.normalize();
+
+#ifdef TEST_INTERNAL_OBJECTS
+				gExpectedNbTests++;
+				if(gUseInternalObject && !TestInternalObjects(transA,transB,DeltaC2, Cross, hullA, hullB, dmin))
+					continue;
+				gActualNbTests++;
+#endif
+
+				float dist;
+				if(!TestSepAxis( hullA, hullB, transA,transB, Cross, dist))
+					return false;
+
+				if(dist<dmin)
+				{
+					dmin = dist;
+					sep = Cross;
+				}
+			}
+		}
+
+	}
+}
+void	btPolyhedralContactClipping::clipFaceContacts(const btVector3& separatingNormal, const btConvexPolyhedron& hullA, const btConvexPolyhedron& hullB, const btTransform& transA,const btTransform& transB, const btScalar maxDist, btDiscreteCollisionDetectorInterface::Result& resultOut)
+{
+
+	btScalar curMaxDist=maxDist;
+	int closestFaceA=-1, closestFaceB=-1;
+
+	{
+		btScalar dmax = -FLT_MAX;
+		for(int face=0;face<hullB.m_faces.size();face++)
+		{
+			const btVector3 Normal(hullB.m_faces[face].m_plane[0], hullB.m_faces[face].m_plane[1], hullB.m_faces[face].m_plane[2]);
+			const btVector3 WorldNormal = transB.getBasis() * Normal;
+
+			btScalar d = WorldNormal.dot(separatingNormal);
+			if (d > dmax)
+			{
+				dmax = d;
+				closestFaceB = face;
+			}
+		}
+	}
+
+	{
+		btScalar dmin = FLT_MAX;
+		for(int face=0;face<hullA.m_faces.size();face++)
+		{
+			const btVector3 Normal(hullA.m_faces[face].m_plane[0], hullA.m_faces[face].m_plane[1], hullA.m_faces[face].m_plane[2]);
+			const btVector3 faceANormalWS = transA.getBasis() * Normal;
+		
+			btScalar d = faceANormalWS.dot(separatingNormal);
+			if (d < dmin)
+			{
+				dmin = d;
+				closestFaceA = face;
+			}
+		}
+	}
+	if (closestFaceA<0 || closestFaceB<0)
+	{
+		return;
+	}
+
+	// setup initial clip face (minimizing face from hull B)
+	btVertexArray worldVertsB1;
+	btVertexArray worldVertsB2;
+
+	btVertexArray* pVtxIn = &worldVertsB1;
+	btVertexArray* pVtxOut = &worldVertsB2;
+	
+	const btFace& polyA = hullA.m_faces[closestFaceA];
+	{
+		const btFace& polyB = hullB.m_faces[closestFaceB];
+		const int numVertices = polyB.m_indices.size();
+		for(int e0=0;e0<numVertices;e0++)
+		{
+			const btVector3& b = hullB.m_vertices[polyB.m_indices[e0]];
+			pVtxIn->push_back(transB*b);
+		}
+	}
+	pVtxOut->reserve(pVtxIn->size());
+
+	// clip polygon to back of planes of all faces of hull A that are adjacent to witness face
+	int numContacts = pVtxIn->size();
+	int numVerticesA = polyA.m_indices.size();
+	for(int e0=0;e0<numVerticesA;e0++)
+	{
+		const btVector3& a = hullA.m_vertices[polyA.m_indices[e0]];
+		const btVector3& b = hullA.m_vertices[polyA.m_indices[(e0+1)%numVerticesA]];
+		const btVector3 edge0 = a - b;
+		const btVector3 WorldEdge0 = transA.getBasis() * edge0;
+		int otherFace = polyA.m_connectedFaces[e0];
+		btVector3 localPlaneNormal (hullA.m_faces[otherFace].m_plane[0],hullA.m_faces[otherFace].m_plane[1],hullA.m_faces[otherFace].m_plane[2]);
+		btScalar localPlaneEq = hullA.m_faces[otherFace].m_plane[3];
+
+		btVector3 planeNormalWS = transA.getBasis()*localPlaneNormal;
+		btScalar planeEqWS=localPlaneEq-planeNormalWS.dot(transA.getOrigin());
+		//clip face
+
+		clipFace(*pVtxIn, *pVtxOut,planeNormalWS,planeEqWS);
+		btSwap(pVtxIn,pVtxOut);
+		pVtxOut->resize(0);
+	}
+
+
+
+//#define ONLY_REPORT_DEEPEST_POINT
+
+	btVector3 point;
+	
+
+	// only keep points that are behind the witness face
+	{
+		btVector3 localPlaneNormal (polyA.m_plane[0],polyA.m_plane[1],polyA.m_plane[2]);
+		btScalar localPlaneEq = polyA.m_plane[3];
+		btVector3 planeNormalWS = transA.getBasis()*localPlaneNormal;
+		btScalar planeEqWS=localPlaneEq-planeNormalWS.dot(transA.getOrigin());
+		for (int i=0;i<pVtxIn->size();i++)
+		{
+			
+			btScalar depth = planeNormalWS.dot(pVtxIn->at(i))+planeEqWS;
+			if (depth <=0)
+			{
+				btVector3 point = pVtxIn->at(i);
+#ifdef ONLY_REPORT_DEEPEST_POINT
+				curMaxDist = depth;
+#else
+#if 0
+				if (depth<-3)
+				{
+					printf("error in btPolyhedralContactClipping depth = %f\n", depth);
+					printf("likely wrong separatingNormal passed in\n");
+				} 
+#endif				
+				resultOut.addContactPoint(separatingNormal,point,depth);
+#endif
+			}
+		}
+	}
+#ifdef ONLY_REPORT_DEEPEST_POINT
+	if (curMaxDist<maxDist)
+	{
+		resultOut.addContactPoint(separatingNormal,point,curMaxDist);
+	}
+#endif //ONLY_REPORT_DEEPEST_POINT
+
+}
\ No newline at end of file
diff --git a/src/BulletCollision/NarrowPhaseCollision/btPolyhedralContactClipping.h b/src/BulletCollision/NarrowPhaseCollision/btPolyhedralContactClipping.h
new file mode 100644
index 000000000..fd96862f7
--- /dev/null
+++ b/src/BulletCollision/NarrowPhaseCollision/btPolyhedralContactClipping.h
@@ -0,0 +1,43 @@
+/*
+Bullet Continuous Collision Detection and Physics Library
+Copyright (c) 2011 Advanced Micro Devices, Inc.  http://bulletphysics.org
+
+This software is provided 'as-is', without any express or implied warranty.
+In no event will the authors be held liable for any damages arising from the use of this software.
+Permission is granted to anyone to use this software for any purpose, 
+including commercial applications, and to alter it and redistribute it freely, 
+subject to the following restrictions:
+
+1. The origin of this software must not be misrepresented; you must not claim that you wrote the original software. If you use this software in a product, an acknowledgment in the product documentation would be appreciated but is not required.
+2. Altered source versions must be plainly marked as such, and must not be misrepresented as being the original software.
+3. This notice may not be removed or altered from any source distribution.
+*/
+
+
+///This file was written by Erwin Coumans
+
+
+#ifndef __POLYHEDRAL_CONTACT_CLIPPING_H
+#define __POLYHEDRAL_CONTACT_CLIPPING_H
+
+
+#include "LinearMath/btAlignedObjectArray.h"
+#include "LinearMath/btTransform.h"
+#include "btDiscreteCollisionDetectorInterface.h"
+
+class btConvexPolyhedron;
+
+typedef btAlignedObjectArray<btVector3> btVertexArray;
+
+// Clips a face to the back of a plane
+struct btPolyhedralContactClipping
+{
+	static void clipFaceContacts(const btVector3& separatingNormal, const btConvexPolyhedron& hullA, const btConvexPolyhedron& hullB, const btTransform& transA,const btTransform& transB, const btScalar maxDist, btDiscreteCollisionDetectorInterface::Result& resultOut);
+
+	static void clipFace(const btVertexArray& pVtxIn, btVertexArray& ppVtxOut, const btVector3& planeNormalWS,btScalar planeEqWS);
+
+	static bool findSeparatingAxis(	const btConvexPolyhedron& hullA, const btConvexPolyhedron& hullB, const btTransform& transA,const btTransform& transB, btVector3& sep);
+};
+
+#endif // __POLYHEDRAL_CONTACT_CLIPPING_H
+