The nice gentleman at Jock Smiths was fantastic at selling me the new SGS2 and the wonderful Leather case to protect the Super Amoled screen with gorilla glass.  I played with compass and gps apps like Compass and Wikitude for ages trying to figure out why it wasn't working.  Removed it from the case and it worked.  Seems the Magnets in the latch on the case are that strong they stop the Compass from working.  Did surgery and removed them and superglued domes on and back in action.