Prepare rice according to package directions. In a large skillet, saute the onion, mushrooms and celery in oil until tender. Remove from the heat; add the rice, pecans, parsley, thyme and marjoram. Stuff hens; rub skin with butter.
Place on a rack in a shallow baking pan. Bake, uncovered, at 350° for 30 minutes.
Meanwhile, for sauce, heat the butter, jelly and lemon juice in a small saucepan until butter and jelly are melted. Combine the cornstarch, vinegar, salt and cloves until smooth; add to pan. Bring to a boil; cook and stir for 2 minutes or until thickened.
After hens have baked for 30 minutes, baste and bake 30 minutes longer or until juices run clear. Place extra stuffing in a greased 1-qt. baking dish; cover and bake at 350° for 30 minutes.