Mix 1-1/2 cups all-purpose flour, rye flour, sugar, salt, caraway seed, orange peel and undissolved yeast in a large bowl. Heat butter and water until very warm; add to dry mixture. Mix in enough remaining all-purpose flour to make a soft dough.
On a floured surface, knead 8 to 10 minutes. Let dough rest 10 minutes. Shape into a ball. Set on greased baking sheet. Cover; let rise in a warm draft-free place until doubled in size, about 30 to 40 minutes. Slash top in crosshatch pattern, making cuts about 5/8 to 3/4-inch deep.
Preheat oven to 400°F. Bake for 30 minutes or until done. Remove from sheet; cool on wire rack.