Error Exporting as an OBJ

I have a simple Blender scene with a mesh that I have imported into the scene, originally, from an OBJ created in another program (Silo). Everything is fine. But I have an armature attached, and I have reposed it. I want to take this new version back into Silo.

So, I apply the armature. Then I select the Object and try to do an export-> OBJ.

I am getting an error:

Traceback (most recent call last):
  File "C:\Blender Foundation\Blender\2.54\scripts\op\io_scene_obj\", line 116, in execute
TypeError: bpy_struct.keys(): this type doesn't support IDProperties

Does anyone know what is causing this?

ACK… Nevermind… appears to be a bug in the previous release that has been fixed in the current one.

I loaded up 2.55 and it works fine.