CRUST: * 1 cup graham cracker crumbs * 1/4 cup chopped walnuts * 2 tbsp. brown sugar * 1 tsp. cinnamon * 1/2 cup melted butter FILLING: * 2 cups sour cream * 3 pkgs. (8 oz.) cream cheese, softened * 3 eggs * 1 cup Sugar * 1/2 tsp. salt * 2 tsp. vanilla * zest of 1/2 orange * 2 1/2 cups mango puree