Washburn Curbow?

Just wondering if anyone else has ever seen one of these? I bought this bass used probably 10 years ago...at the time I emailed Washburn to get info but they seemed baffled about it too. The model number is X-4000, and Im thinkin it may be a "one-off" or pre-production model with Curbow prior to the Cort models. I have included pics of it with my Cort Curbow 6 string.