Preheat oven to 350°.
Place apple juice in a small microwave-safe bowl; microwave at HIGH for 3 minutes or until juice boils. Remove from microwave. Add currants and dried apple; let stand 15 minutes.
Combine the buttermilk, sugar, margarine, and apple juice mixture in a large bowl. Lightly spoon flour into dry measuring cups, and level with a knife. Combine the flour, walnuts, baking powder, baking soda, and salt; add to buttermilk mixture, stirring just until moist (dough will be sticky). Drop the dough into 12 rounds (about 1/4 cup) onto a baking sheet coated with cooking spray. Bake at 350° for 17 minutes or until golden. Place on a wire rack.