Preheat oven to 375F. Place berries in a 9-inch square baking dish. In a small bowl, combine brown sugar, flour, and cinnamon. Stir lightly into fruit. For Topping, combine all ingredients except butter and nuts. With a pastry blender, cut into butter until mixture resembles coarse crumbs. Add nuts. Sprinkle topping over berries. Bake 30 minutes or until bubbly around edge.
Notes: I doubled the topping for this. It was very excellent for 3 days.