 						jointSkinningMatrix	= getFieldFromArray(jointId.x, skinningMatrices, true);
 						jointOutNormal		= multiply3x3(inVertexNormal, jointSkinningMatrix);
 						jointOutNormal		= multiply(jointAttr.y, jointOutNormal);
-						outVertexNormal.incrementBy(jointOutNormal);
+//                        outVertexNormal.incrementBy(jointOutNormal)
+						outVertexNormal = outVertexNormal
+                            ? outVertexNormal.incrementBy(jointOutNormal)
+                            : jointOutNormal;
 						
 						jointSkinningMatrix	= getFieldFromArray(jointId.y, skinningMatrices, true);
 						jointOutNormal		= multiply3x3(inVertexNormal, jointSkinningMatrix);

				}
				else
				{
					outVertexPosition = float4(0, 0, 0, 0);
					
					var jointOutVertexPosition : SFloat;
					for (var i : uint = 0; i < (maxInfluences >> 1); ++i)

						jointSkinningMatrix		= getFieldFromArray(jointId.x, skinningMatrices, true);
						jointOutVertexPosition	= multiply4x4(inVertexPosition, jointSkinningMatrix);
						jointOutVertexPosition	= multiply(jointAttr.y, jointOutVertexPosition);
						outVertexPosition = outVertexPosition
                            ? outVertexPosition.incrementBy(jointOutVertexPosition)
                            : jointOutVertexPosition;
						
						jointSkinningMatrix		= getFieldFromArray(jointId.y, skinningMatrices, true);
						jointOutVertexPosition	= multiply4x4(inVertexPosition, jointSkinningMatrix);
