Combine all ingredients except butter or margarine. Line a 9" pie plate with Orange Pastry**. Fill with rhubarb mixture and dot with the butter or margarine. Top with lattice crust. Bake at 400 degrees 40 to 50 minutes. Serve warm with vanilla ice cream. ** Substitute orange juice for the water in your favorite pastry recipe. Source: Better Homes & Gardens Dessert Cookbook.