Preheat oven to 350F. Grease some cookie sheets. Set aside. Mix together the flour, oatmeal, bran, sugar & spices in a bowl. Rub in the margarine until the mixture resembles coarse breadcrumbs. Add enough water to make a stiff dough. Roll out the dough on a floured board to a thickness of 1/2". Cut into rounds, 2" to 3" across. Place on baking sheets. Bake for 25 minutes. Lift carefully onto a wire rack to cool.