Bring 2 quarts water to a boil in a large saucepan. Add pasta, and cook, uncovered, 9 minutes. Add shrimp; cook, uncovered, 3 minutes or until shrimp turn pink. Place pea pods in a colander. Drain pasta over pea pods.
Transfer mixture to a large serving bowl. Add onions, vinaigrette, and pepper; toss lightly. Sprinkle with crumbled feta cheese.