 				tx = tangentsData.readFloat();
 				ty = tangentsData.readFloat();
 				tz = tangentsData.readFloat();
-				mag = Math.sqrt(tx * tx + ty * ty + tz * tz);
+				
+				var mag : Number = Math.sqrt(tx * tx + ty * ty + tz * tz);
 				
 				if (mag != 0.)
 				{

					if (computeNormals)
						fillNormalsData(indices, normalsStream, xyzStream, triangles);
					
					if (!hasNormals)
						pushVertexStreamInList(streamId, normalsStream);
					if (!hasTangents && tangentsStream != normalsStream)
						pushVertexStreamInList(streamId, tangentsStream);

				tangentsData.position = ii;
				var tx1 : Number = tx + tangentsData.readFloat();
				var ty1 : Number = ty + tangentsData.readFloat();
				var tz1 : Number = tz + tangentsData.readFloat();
				
				tangentsData.position = ii;
				tangentsData.writeFloat(tx1);
