Place raisins into a saucepan and cover with water. Bring to a boil, reduce heat and simmer until plump; drain and set aside. Preheat oven to 325 degrees Fahrenheit. Spray two 9" by 5" loaf pans with cooking spray and set aside.
In a large bowl, mix together the mashed sweet potatoes, brown sugar, granulated sugar, orange juice, milk, eggs, and cooled melted butter. Sift the flour, baking soda, cinnamon and grated nutmeg into a bowl; add the nuts and raisins and toss to coat them. Add the dry mixture to the wet, and blend together. Spoon evenly into the two prepared loaf pans and add the topping (see below).
Bake at 325 degrees Fahrenheit for about 55 minutes to 1 hour, or until a toothpick inserted into the center of the bread comes out clean. Cool the bread in the pan on a cooling rack for about 15 minutes, then turn out, taking care not to knock off the topping, and allow to cool completely on the rack. Serve with honey butter.
Crumble the butter into the flour; add in the brown sugar, oats and pecans. Sprinkle evenly on top of the batter of both loaves and lightly pat it into the batter. Bake as noted above.