Well, you can't, but your bear can :0.   Nothing to make his claws magical?  With a level 3 druid spell and a hit from a 3k lesser metamagic rod, I could make his claws +1 for a day as part of my daily ritual...I can afford the rod slot as the low light vision I'm using it for now is almost always meaningless, though fitting the level 3 spell in would be rougher.