Preheat the oven to 375'F. In a mixing bowl, combine all the ingredients. Add the beer all at once, mixing as little as possible; the batter should be lumpy. Pour the batter into a 9-x-5-x-3-inch loaf pan and brush with the melted butter. Bake in the oven for 35 to 40 minutes, or until an inserted skewer comes out clean. Turn out onto a rack to cool.