What does "cardctl ident" or "cardctl status" report? Maybe you have to wake up the card first ("cardctl resume 0") in order to use it... Also, in the past, I've played with GPS cards on other devices, some were very long to get a fix, maybe the card won't give any data until it has found exactly where it is located? Are you in a place with a good satellite reception (outdoor, for instance)?
Hope you'll get it working, I certainly would be interested by such a card, too...