It took quite a while, but by now it is out. Please welcome the Windows CardSpace Information Card extensions for OpenSSO:
https://opensso.dev.java.net/source/browse/opensso/extensions/authnicip/
When I started working on this last spring, I was not even hoping to see this released in open source and part of the OpenSSO extensions family in less than a year. It took the goodwill and talent of quite a few people to get this off the ground, but with the public release of this code and the upcoming OSIS interop during the RSA onference, OpenSSO is now “speaking ISIP” …