Read or Die OVA, Stephen?

I just bought the R.O.D. OVA, and one of the extra features was mini-biographies on the I-jin. The thing is, it was one person short. The name Stephen is written on a piece of the glider, and after a comment about steam when the cloud Ganjou was riding on ran out, Joker wrote Stephen on his list of I-jin. I assume that the old man operating the fortress at the end is this Stephen, but who is he supposed to be?

The list was for researching the Great Men so I figure it’d be a Stephen who knew how to design steam driven devices.

Edit: Found this :