Crust: In a blender, process Grape-Nuts into crumbs. Combine all ingredients. Press into a 9" springform pan. Bake at 350 F (180 C) for 10 minutes. Cool.
Filling: In a food processor or blender with a sharp blade, process ricotta cheese until smooth. Add creanm cheese and eggs. Beat. Add the remaining ingredients. Beat until smooth. Pour over the graham craker crust and bake about 40 minutes in a 350 F (180 C) oven.
Raspberry Topping: In a saucepan, combine the juice, cornstarch and Splenda granular. Stir until smooth and cook, stirring until it begins to thicken. Stir in 1 package of raspberries and cook until the sauce is thick. Remove from heat and stir in the remaining raspberries. Pour over cheesecake and refrigerate overnight.