The current FC4 Extras ufraw package is 0.4, and doesn't recognize the .cr2 files I got from a friend's Canon camera. I just tried 0.6 and that version works, I can import the files just fine in the GIMP. So it seems updating the Extras package (FC4 & devel at least) would be a good thing since it would have support for more cameras.
From bug #169769: """ As ufraw-0.5 removes a command line option present in 0.4.x ("ufraw --batch" becomes "ufraw-batch"), I'll only update the development tree which should become FC5 Extras in time. """ *** This bug has been marked as a duplicate of 173753 ***