Cook rhubarb, sugar, cornstarch and salt until thick. Pour into unbaked pie shell. Bake 425F 10 minutes. Mix cream cheese, sugar and eggs until creamy. Pour on top of rhubarb. Filling will puff up as it bakes if it completely fills the crust it will spill over. Instead of a decorative pie shell edge I pinch it every couple of inches to make it stand up. Bake at 350F for 30 minutes. If you bake it until the filling is lightly browned and the center looks done it will be over-cooked.