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Traceback (most recent call last):
  File "C:\xxxx\3D\Blender\blender-2.65a-windows32\2.65\scripts\addons\io_scene_md3\__init__.py", line 55, in execute
    export_md3.exportMD3(context, self.properties.filepath)
  File "C:\xxxx\3D\Blender\blender-2.65a-windows32\2.65\scripts\addons\io_scene_md3\export_md3.py", line 368, in exportMD3
    write_n_items(ctx, file, len(ctx['surfNames']), write_surface)
  File "C:\xxxx\3D\Blender\blender-2.65a-windows32\2.65\scripts\addons\io_scene_md3\export_md3.py", line 56, in write_n_items
    func(ctx, i, file)
  File "C:\xxxx\3D\Blender\blender-2.65a-windows32\2.65\scripts\addons\io_scene_md3\export_md3.py", line 283, in write_surface
    ctx['mesh'].calc_normals_split()
AttributeError: 'Mesh' object has no attribute 'calc_normals_split'

location: <unknown location>:-1