Cook rice according to package directions. Fry sliced onion in 2 tb butter until transparent. Cut eggplant into 1/2 inch slices, sprinkle with salt and let stand 10 minutes. Remove onion from pan. Fry eggplant in same pan with 4 tb butter. Combine all ingredients in large buttered casserole. Add tomato juice, cover with cheese and buttered crumbs. Place in 350 degree oven for 15 to 20 minutes or until golden brown.