CLAMP response bug

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        // ************************************************************************
	//
	// Add your custom code here...
	//
	// ************************************************************************
	
	t2dScene.setConstantForce("0 50",true);
	t2dScene.setDebugOn(255);
	
	
	$floor = new t2dStaticSprite() {scenegraph = t2dScene;};
	
	$floor.setImageMap(imageMap1234);
	$floor.setImmovable( true );
	$floor.setPosition("0 25");
	$floor.setSize("80 10");
	$floor.setGroup(1);
	$floor.setCollisionPolyPrimitive(4);
	$floor.setCollisionActive(true,true);
	$floor.setCollisionPhysics(true,true);
	$floor.setCollisionResponse( CLAMP );

	
	$obj = new t2dStaticSprite() {scenegraph = t2dScene;};	
	$obj.setImageMap(imageMap1234);
	$obj.setFrame(1);
	$obj.setPosition("0 0");
	$obj.setSize("10 10");
	$obj.setCollisionMasks(BIT(1));
	$obj.setCollisionPolyPrimitive(4);
	$obj.setCollisionActive(true,true);
	$obj.setCollisionPhysics(true,true);
	$obj.setCollisionResponse( CLAMP );

	$actionmap = new ActionMap();
	$actionmap.bindCmd(keyboard,"a","$obj.setLinearVelocityX(-50);","$obj.setLinearVelocityX(0);");
	$actionmap.bindCmd(keyboard,"d","$obj.setLinearVelocityX(50);","$obj.setLinearVelocityX(0);");
	$actionmap.bindCmd(keyboard,"w","$obj.setImpulseForce(\"0 -100\");","");
	$actionmap.push();