Combine flour, baking soda, baking powder and salt. With your hands, rub the butter through the dry ingredients (above) until crumbly. Add sugar and oats; mix well. Spread 1/2 of the mixture into a greased 9 inch square pan. Press the mixture until smooth and firm. Place the partridgeberries in a saucepan. Add the water; boil 5-10 min. until thickened. Add sugar and stir until sugar is dissolved. Cook for another 5 min. until thick. Remove from heat. Let cool. Spread the cool partridgeberry filling over the base. Spread the remaining dry mixture over the top of the filling. Bake at 350 degrees for 35-40 min. until golden brown.