Seems luck is on my side tonight. After a bad start with no controls being sent, I finally worked out how to make cps2 work over wifi..
http://www.youtube.com/watch?v=yLv26jEX6lk
I've cleaned up the adhoc connection code too now, so it all fits in nicely with NJ's original emulator
As requested, the video is of street fighter alpha 2. I apologise once again for the video quality...