Combine tomato and water in a small bowl; cover and let stand 15 minutes. Drain well. Chop tomato, and set aside.

Cook pasta according to package directions, omitting salt and fat. Drain; rinse with cold water, and drain. Combine tomato, pasta, cheese, and zucchini, tossing gently.

Combine vinegar and remaining ingredients, stirring well with a wire whisk. Add vinegar mixture to pasta mixture, and toss gently. Cover and chill 1 hour. Toss gently before serving.