Cook pasta according to package directions, omitting salt and fat; drain.
While pasta cooks, heat oil in a nonstick skillet over medium heat. Add onion, and sauté 4 minutes or until tender. Add garlic; sauté 1 minute. Add tomatoes, salt, and pepper. Cook 3 minutes, stirring often. Add wine and lemon juice; reduce heat, and simmer 3 minutes. Stir in parsley and clams. Combine pasta and sauce, and toss well to coat.