You did try to install it the correct way . There's a little catch however.

Fcam-drivers-bfs conflicts with, replaces, and provides fcam-drivers. You appear to have an application installed which depends on the fcam-drivers (namely blessn900). Prior to installing fcam-drivers-bfs, fcam-drivers needs to be removed (since we try to replace it), Now this application that depends on fcam-drivers starts to complain, even though we're about to install a package that provides the same functionality!

You can make dpkg automatically deconfigure and reconfigure the applications that depend on fcam-drivers, so that the those applications won't complain in the little time span the fcam-drivers package is removed. To do this, you'll have to run:

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edit: the most ideal situation is that the official fcam-drivers will get support for kernel-bfs. But this can't be done before kernel-bfs is pushed to the repositories since fcam-drivers will depend on kernel-bfs-headers then. Until that time, we'll have to do with our own package . I'll try to contact the maintainer of the fcam-drivers package when kernel-bfs hits the repositories.


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Update: Kernel-bfs has just hit the repos! The new kernel-bfs [Announce] thread can be found here:
http://talk.maemo.org/showthread.php?p=1099211