Preheat oven to 400 degrees (convection bake. If you're using a standard oven, you can do 425.)Zest two of the lemons. Strip the leaves off of one of the rosemary sprigs and chop it up finely.In a bowl, combine softened butter, lemon zest, rosemary, and salt and pepper to taste.Line a baking sheet with heavy duty aluminum foil and lay the patted-dry chicken on the foil, breast side up. Use your fingers to smear the butter mixture all over the chicken, under the skin, and inside the cavity. Cut the lemons in half and squeeze the juice of one lemon all over the chicken. Place the six lemon halves (if they'll fit!) and the three remaining rosemary leaves into the cavity of the bird. Place the chicken into the oven and roast it for 1 hour, 15 minutes or until done. Skin should be deep golden brown and juices should be sizzling. Carve/cut up to your heart's content and dig in!