Reply by tenontim

If you look at cedar chest in the antique stores, you see they weren’t finished on the inside. I think that due to the fact that the chest are closed most of the time, and the items in them soak up more moisture than the wood, you don’t have any problems with warping. If you’re worried about warping, finish the sides and leave the bottom unfinished. If you put anything, other than cedar oil, on the wood, it WILL seal the aroma in the wood, and you’ll have an un-aromatic cedar chest.

-- Tim-- http://www.tmuli.com