Bring water to a rolling boil. Add pasta; cook 12 minutes. Drain; set aside, and keep warm.
Heat butter and olive oil in a large nonstick skillet over medium heat. Sprinkle flour over shrimp, tossing to coat well. Add shrimp to skillet; cook, stirring constantly, 4 minutes or until shrimp turn pink and are lightly browned. Remove shrimp from skillet; set aside, and keep warm.
Add garlic and rosemary to skillet; cook 1 minute. Add wine, lemon juice, and tomatoes. Increase heat to high, and cook 7 minutes or until most of liquid evaporates. Return shrimp to skillet; cook just until heated. Add green onions, salt, and pepper. Serve over pasta.