Cook pasta and rinse in cold water. Drain, lay out in a single layer so they don't stick together. Set aside. Cook sausage, ground beef, and onion in a large skillet, stirring until meat crumbles and is no longer pink. Drain, remove meat from skillet, and set aside.

For the sauce, add white grape juice to skillet; bring to a boil. Add whipping cream and next three ingredients; reduce heat and simmer, stirring often, 15 minutes or until thickened. Remove from heat, cover and set aside.

Combine meat mixture, tomatoes, and mozzarella cheese. Spoon mixture evenly into 12 manicotti shells; arrange shells in a lightly greased 9 by 13 inch pan. Bake, covered, at 350 degrees for 20 mintues. Unover and pour cream mixture evenly over shells. Sprinkle with parmasean cheese. Bake, uncovered, at 350 for 10 to 12 more minutes.