In a large stock pot or container, mix water, salt, brown sugar and Kikkoman Soy Sauce to create brine. Stir well until the sugar and salt are dissolved. Add the juice from the orange and lemon and the chopped rosemary; stir to combine. Place the hens in the brine, cover and refrigerate for at least 2 hours or overnight. Remove hens from the brine and rinse well inside and out; pat dry. Rub skin all over with olive oil, and sprinkle with a little salt and pepper. Place in a baking dish, breast sides up. Bake at 350°F for about 1 hour and 30 minutes, or until no longer pink at the bone.