Don't you have to be lawful as a werebear? My books aren't handy at the moment but I think that werebears are 'always' LG as opposed to 'usually' LG. This would mean that you couldn't take barbarian as a natural werebear.
However, further in the description on p178 under "Creating a Lycanthrope":
Alignment: Any. Noble creatures such as bears, eagles, and lions tend to produce good-aligned lycanthropes. Sinister creatures such as rats, snakes, and wolves tend to produce evil-aligned lycanthropes. This is a reflection of how these animals are perceived, not any innate quality of the animal itself, so the alignment of the animal form can be arbitrarily assigned.
And then further under "Lycanthropes as characters":
Becoming a lycanthrope does not change a character’s favored class but usually changes alignment (see above). This alignment change may cause characters of certain classes to lose some of their class features.
