Place olive oil, butter, garlic, onion and sausage in a large saucepan. Saute until sausage is browned and onion is transparent. (Drain grease if you like.) Add eggplant, green and red pepper, and zucchini. Cook until slightly tender. Add crushed tomatoes, sugar, fresh basil, oregano and salt and pepper. Cook another 5 minute until simmering.