In large saucepan, combine 1/4 cup water, 1/4 cup of the sugar, the lemon juice and cornstarch; stir until smooth. Add raspberries and blueberries; cook, stirring constantly, until mixture boils 1 minute and thickens slightly. Set aside. Preheat oven to 350°F. Spray an 8 square baking pan with nonstick cooking spray. In large bowl, with electric mixer, beat remaining 1/4 cup sugar and margarine until light and fluffy. Add egg and vanilla; beat until smooth. On wax paper, combine flour, baking powder and salt. Add dry ingredients to margarine mixture alternately with milk, beating until smooth. Remove 1/4 cup batter and reserve. Spread remaining batter evenly into bottom of prepared pan. Spread berry mixture over batter. Drop reserved batter by teaspoonfuls over berries in several places; spoon reserved berries over top. 4. Bake 20 minutes; reduce heat to 300°F and bake 20-25 minutes longer, until batter on top is golden. Let stand at least 20 minutes before serving. Each serving provides: 1 FA, 1/2 B, 1/2 FR, 50 C. Per serving: 152 cal, 2 g pro, 5 g fat, 26 g car, 155 mg sod, 18 mg chol. DESS 188