That's the one for RunUO2, try this one
http://xmlspawner.15.forumer.com/index.php?showtopic=4
I think I had some sucess with it on SunUO 0.5.0...
Hope this helps...
If not then it would be nice for someone to post a guide or release a working version on this forum...
Or even include a spawner with SunUO, after all they are all open source; or is there a reason it hasn't been done yet?
Merry Christmas!