diff --git a/Demos/UserCollisionAlgorithm/SphereSphereCollisionAlgorithm.cpp b/Demos/UserCollisionAlgorithm/SphereSphereCollisionAlgorithm.cpp
new file mode 100644
index 000000000..52beffaef
--- /dev/null
+++ b/Demos/UserCollisionAlgorithm/SphereSphereCollisionAlgorithm.cpp
@@ -0,0 +1,81 @@
+/*
+Bullet Continuous Collision Detection and Physics Library
+Copyright (c) 2003-2006 Erwin Coumans  http://continuousphysics.com/Bullet/
+
+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.
+*/
+
+#include "SphereSphereCollisionAlgorithm.h"
+#include "CollisionDispatch/CollisionDispatcher.h"
+#include "CollisionShapes/SphereShape.h"
+#include "CollisionDispatch/CollisionObject.h"
+
+SphereSphereCollisionAlgorithm::SphereSphereCollisionAlgorithm(PersistentManifold* mf,const CollisionAlgorithmConstructionInfo& ci,BroadphaseProxy* proxy0,BroadphaseProxy* proxy1)
+: CollisionAlgorithm(ci),
+m_ownManifold(false),
+m_manifoldPtr(mf)
+{
+	if (!m_manifoldPtr && m_dispatcher->NeedsCollision(*proxy0,*proxy1))
+	{
+		m_manifoldPtr = m_dispatcher->GetNewManifold(proxy0->m_clientObject,proxy1->m_clientObject);
+		m_ownManifold = true;
+	}
+}
+
+SphereSphereCollisionAlgorithm::~SphereSphereCollisionAlgorithm()
+{
+	if (m_ownManifold)
+	{
+		if (m_manifoldPtr)
+			m_dispatcher->ReleaseManifold(m_manifoldPtr);
+	}
+}
+
+void SphereSphereCollisionAlgorithm::ProcessCollision (BroadphaseProxy* proxy0,BroadphaseProxy* proxy1,const DispatcherInfo& dispatchInfo)
+{
+	if (!m_manifoldPtr)
+		return;
+
+	CollisionObject*	col0 = static_cast<CollisionObject*>(proxy0->m_clientObject);
+	CollisionObject*	col1 = static_cast<CollisionObject*>(proxy1->m_clientObject);
+	SphereShape* sphere0 = (SphereShape*)col0->m_collisionShape;
+	SphereShape* sphere1 = (SphereShape*)col1->m_collisionShape;
+
+	SimdVector3 diff = col0->m_worldTransform.getOrigin()-  col1->m_worldTransform.getOrigin();
+	float len = diff.length();
+	SimdScalar radius0 = sphere0->GetRadius();
+	SimdScalar radius1 = sphere1->GetRadius();
+
+	///iff distance positive, don't generate a new contact
+	if ( len > (radius0+radius1))
+		return;
+
+	///distance (negative means penetration)
+	SimdScalar dist = len - (radius0+radius1);
+
+	SimdVector3 normalOnSurfaceB = diff / len;
+	///point on A (worldspace)
+	SimdVector3 pos0 = col0->m_worldTransform.getOrigin() - radius0 * normalOnSurfaceB;
+	///point on B (worldspace)
+	SimdVector3 pos1 = col1->m_worldTransform.getOrigin() + radius1* normalOnSurfaceB;
+
+	/// report a contact. internally this will be kept persistent, and contact reduction is done
+	ManifoldResult* resultOut = m_dispatcher->GetNewManifoldResult(col0,col1,m_manifoldPtr);
+	resultOut->AddContactPoint(normalOnSurfaceB,pos1,dist);
+	m_dispatcher->ReleaseManifoldResult(resultOut);
+
+}
+
+float SphereSphereCollisionAlgorithm::CalculateTimeOfImpact(BroadphaseProxy* proxy0,BroadphaseProxy* proxy1,const DispatcherInfo& dispatchInfo)
+{
+	//not yet
+	return 1.f;
+}
diff --git a/Demos/UserCollisionAlgorithm/SphereSphereCollisionAlgorithm.h b/Demos/UserCollisionAlgorithm/SphereSphereCollisionAlgorithm.h
new file mode 100644
index 000000000..954e9c380
--- /dev/null
+++ b/Demos/UserCollisionAlgorithm/SphereSphereCollisionAlgorithm.h
@@ -0,0 +1,54 @@
+/*
+Bullet Continuous Collision Detection and Physics Library
+Copyright (c) 2003-2006 Erwin Coumans  http://continuousphysics.com/Bullet/
+
+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.
+*/
+
+#ifndef SPHERE_SPHERE_COLLISION_ALGORITHM_H
+#define SPHERE_SPHERE_COLLISION_ALGORITHM_H
+
+#include "BroadphaseCollision/CollisionAlgorithm.h"
+#include "BroadphaseCollision/BroadphaseProxy.h"
+#include "CollisionDispatch/CollisionCreateFunc.h"
+class PersistentManifold;
+
+/// SphereSphereCollisionAlgorithm  provides sphere-sphere collision detection.
+/// Other features are frame-coherency (persistent data) and collision response.
+/// Also provides the most basic sample for custom/user CollisionAlgorithm
+class SphereSphereCollisionAlgorithm : public CollisionAlgorithm
+{
+	bool	m_ownManifold;
+	PersistentManifold*	m_manifoldPtr;
+	
+public:
+	SphereSphereCollisionAlgorithm(const CollisionAlgorithmConstructionInfo& ci)
+		: CollisionAlgorithm(ci) {}
+
+	virtual void ProcessCollision (BroadphaseProxy* proxy0,BroadphaseProxy* proxy1,const DispatcherInfo& dispatchInfo);
+
+	virtual float CalculateTimeOfImpact(BroadphaseProxy* proxy0,BroadphaseProxy* proxy1,const DispatcherInfo& dispatchInfo);
+
+	SphereSphereCollisionAlgorithm(PersistentManifold* mf,const CollisionAlgorithmConstructionInfo& ci,BroadphaseProxy* proxy0,BroadphaseProxy* proxy1);
+
+	virtual ~SphereSphereCollisionAlgorithm();
+
+	struct CreateFunc :public 	CollisionAlgorithmCreateFunc
+	{
+		virtual	CollisionAlgorithm* CreateCollisionAlgorithm(CollisionAlgorithmConstructionInfo& ci, BroadphaseProxy* proxy0,BroadphaseProxy* proxy1)
+		{
+			return new SphereSphereCollisionAlgorithm(0,ci,proxy0,proxy1);
+		}
+	};
+
+};
+
+#endif //SPHERE_SPHERE_COLLISION_ALGORITHM_H
\ No newline at end of file
diff --git a/Demos/UserCollisionAlgorithm/UserCollisionAlgorithm.cpp b/Demos/UserCollisionAlgorithm/UserCollisionAlgorithm.cpp
new file mode 100644
index 000000000..06985eae6
--- /dev/null
+++ b/Demos/UserCollisionAlgorithm/UserCollisionAlgorithm.cpp
@@ -0,0 +1,214 @@
+/*
+Bullet Continuous Collision Detection and Physics Library
+Copyright (c) 2003-2006 Erwin Coumans  http://continuousphysics.com/Bullet/
+
+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.
+*/
+
+#include "CcdPhysicsEnvironment.h"
+#include "CcdPhysicsController.h"
+
+#include "CollisionShapes/BoxShape.h"
+#include "CollisionShapes/SphereShape.h"
+
+
+#include "CollisionShapes/Simplex1to4Shape.h"
+#include "Dynamics/RigidBody.h"
+#include "BroadphaseCollision/AxisSweep3.h"
+
+#include "ConstraintSolver/SequentialImpulseConstraintSolver.h"
+#include "CollisionDispatch/CollisionDispatcher.h"
+#include "BroadphaseCollision/SimpleBroadphase.h"
+#include "CollisionShapes/TriangleMeshShape.h"
+#include "CollisionShapes/TriangleIndexVertexArray.h"
+#include "CollisionShapes/BvhTriangleMeshShape.h"
+#include "CollisionShapes/TriangleMesh.h"
+#include "IDebugDraw.h"
+#include "GLDebugDrawer.h"
+#include "PHY_Pro.h"
+#include "UserCollisionAlgorithm.h"
+#include "GL_ShapeDrawer.h"
+#include "GlutStuff.h"
+
+//The user defined collision algorithm
+#include "SphereSphereCollisionAlgorithm.h"
+
+GLDebugDrawer	debugDrawer;
+
+static const int NUM_VERTICES = 5;
+static const int NUM_TRIANGLES=4;
+
+SimdVector3	gVertices[NUM_VERTICES];
+int	gIndices[NUM_TRIANGLES*3];
+const float TRIANGLE_SIZE=80.f;
+
+
+///User can override this material combiner by implementing gContactAddedCallback and setting body0->m_collisionFlags |= CollisionObject::customMaterialCallback;
+inline SimdScalar	calculateCombinedFriction(float friction0,float friction1)
+{
+	SimdScalar friction = friction0 * friction1;
+
+	const SimdScalar MAX_FRICTION  = 10.f;
+	if (friction < -MAX_FRICTION)
+		friction = -MAX_FRICTION;
+	if (friction > MAX_FRICTION)
+		friction = MAX_FRICTION;
+	return friction;
+
+}
+
+inline SimdScalar	calculateCombinedRestitution(float restitution0,float restitution1)
+{
+	return restitution0 * restitution1;
+}
+
+
+
+
+
+
+int main(int argc,char** argv)
+{
+
+	UserCollisionAlgorithm* userCollisionAlgorithm = new UserCollisionAlgorithm;
+	userCollisionAlgorithm->initPhysics();
+	userCollisionAlgorithm->setCameraDistance(30.f);
+
+	return glutmain(argc, argv,640,480,"Static Concave Mesh Demo",userCollisionAlgorithm);
+}
+
+void	UserCollisionAlgorithm::initPhysics()
+{
+	#define TRISIZE 10.f
+
+	int vertStride = sizeof(SimdVector3);
+	int indexStride = 3*sizeof(int);
+
+	const int NUM_VERTS_X = 50;
+	const int NUM_VERTS_Y = 50;
+	const int totalVerts = NUM_VERTS_X*NUM_VERTS_Y;
+	
+	const int totalTriangles = 2*(NUM_VERTS_X-1)*(NUM_VERTS_Y-1);
+
+	SimdVector3*	gVertices = new SimdVector3[totalVerts];
+	int*	gIndices = new int[totalTriangles*3];
+
+	int i;
+
+	for ( i=0;i<NUM_VERTS_X;i++)
+	{
+		for (int j=0;j<NUM_VERTS_Y;j++)
+		{
+			gVertices[i+j*NUM_VERTS_X].setValue((i-NUM_VERTS_X*0.5f)*TRIANGLE_SIZE,2.f*sinf((float)i)*cosf((float)j),(j-NUM_VERTS_Y*0.5f)*TRIANGLE_SIZE);
+		}
+	}
+
+	int index=0;
+	for ( i=0;i<NUM_VERTS_X-1;i++)
+	{
+		for (int j=0;j<NUM_VERTS_Y-1;j++)
+		{
+			gIndices[index++] = j*NUM_VERTS_X+i;
+			gIndices[index++] = j*NUM_VERTS_X+i+1;
+			gIndices[index++] = (j+1)*NUM_VERTS_X+i+1;
+
+			gIndices[index++] = j*NUM_VERTS_X+i;
+			gIndices[index++] = (j+1)*NUM_VERTS_X+i+1;
+			gIndices[index++] = (j+1)*NUM_VERTS_X+i;
+		}
+	}
+	
+	TriangleIndexVertexArray* indexVertexArrays = new TriangleIndexVertexArray(totalTriangles,
+		gIndices,
+		indexStride,
+		totalVerts,(float*) &gVertices[0].x(),vertStride);
+
+	CollisionShape* trimeshShape  = new BvhTriangleMeshShape(indexVertexArrays);
+		
+
+	
+	ConstraintSolver* solver = new SequentialImpulseConstraintSolver;
+	
+	CollisionDispatcher* dispatcher = new	CollisionDispatcher();
+		
+	OverlappingPairCache* broadphase = new SimpleBroadphase();
+	dispatcher->RegisterCollisionCreateFunc(SPHERE_SHAPE_PROXYTYPE,SPHERE_SHAPE_PROXYTYPE,new SphereSphereCollisionAlgorithm::CreateFunc);
+	
+
+	m_physicsEnvironmentPtr = new CcdPhysicsEnvironment(dispatcher,broadphase);
+	
+		bool isDynamic = false;
+	float mass = 0.f;
+	SimdTransform	startTransform;
+	startTransform.setIdentity();
+	startTransform.setOrigin(SimdVector3(0,-2,0));
+
+	CcdPhysicsController* staticTrimesh = LocalCreatePhysicsObject(isDynamic, mass, startTransform,trimeshShape);
+	//enable custom material callback
+	staticTrimesh->GetRigidBody()->m_collisionFlags |= CollisionObject::customMaterialCallback;
+
+	{
+		for (int i=0;i<10;i++)
+		{
+			CollisionShape* sphereShape = new SphereShape(1);
+			startTransform.setOrigin(SimdVector3(1,2*i,1));
+			CcdPhysicsController* boxRigidBody = LocalCreatePhysicsObject(true, 1, startTransform,sphereShape);
+		}
+	}
+	m_physicsEnvironmentPtr->setGravity(-1,-10,1);
+	
+	m_physicsEnvironmentPtr->setDebugDrawer(&debugDrawer);
+}
+
+void UserCollisionAlgorithm::clientMoveAndDisplay()
+{
+	 glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT); 
+
+	float deltaTime = 1.f/60.f;
+
+	m_physicsEnvironmentPtr->proceedDeltaTime(0.f,deltaTime);
+	
+	renderme();
+
+    glFlush();
+    glutSwapBuffers();
+
+}
+
+void	UserCollisionAlgorithm::clientResetScene()
+{
+	int numObj = m_physicsEnvironmentPtr->GetNumControllers();
+
+	//skip ground
+	for (int i=1;i<numObj;i++)
+	{
+		CcdPhysicsController* ctrl = m_physicsEnvironmentPtr->GetPhysicsController(i);
+		ctrl->setPosition(1,2*i,1);
+		ctrl->setOrientation(0,0,0,1);
+		ctrl->SetLinearVelocity(0,0,0,0);
+		ctrl->SetAngularVelocity(0,0,0,0);
+	}
+}
+
+
+
+
+void UserCollisionAlgorithm::displayCallback(void) {
+
+    glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT); 
+
+	renderme();
+
+    glFlush();
+    glutSwapBuffers();
+}
+
+
diff --git a/Demos/UserCollisionAlgorithm/UserCollisionAlgorithm.h b/Demos/UserCollisionAlgorithm/UserCollisionAlgorithm.h
new file mode 100644
index 000000000..7730a98e6
--- /dev/null
+++ b/Demos/UserCollisionAlgorithm/UserCollisionAlgorithm.h
@@ -0,0 +1,35 @@
+/*
+Bullet Continuous Collision Detection and Physics Library
+Copyright (c) 2003-2006 Erwin Coumans  http://continuousphysics.com/Bullet/
+
+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.
+*/
+#ifndef USER_COLLISION_ALGORITHM_DEMO_H
+#define USER_COLLISION_ALGORITHM_DEMO_H
+
+#include "DemoApplication.h"
+
+///UserCollisionAlgorithmDemo shows how to register and use your own collision algorithm for a certain shape pair type
+class UserCollisionAlgorithm : public DemoApplication
+{
+	public:
+
+	void	initPhysics();
+
+	virtual void clientMoveAndDisplay();
+
+	virtual void displayCallback();
+	
+	virtual void	clientResetScene();
+	
+};
+
+#endif //USER_COLLISION_ALGORITHM_DEMO_H
\ No newline at end of file