I've been digging and may have found a few things.

The first link is what appears to be the patent for the AT assist device.

http://www.freepatentsonline.com/6328673.html

The second link is an abstract from Hitachi on it

http://www.hitachi.com/rev/1995/Review-Jun/HR304.html

Hopefully this is the same device, I'm going to be sending some e-mail to Hitachi's automotive department and hopefully I'll get a response. Sounds expensive though, especially when patented algorithms are involved.

 

I found these as well for stateside use, looks like a lot of work, harness uilds are needed, and can probably screw up the trans.

http://www.powertraincontrolsolution...content-4.html

http://www.tciauto.com/Products/Electronics/

What is the model of transmission the xB uses?

 

That is very interesting. I would get that just for an option of paddle shifting alone.