Cook pasta according to package directions. Add shrimp during the last 3 minutes of cooking time. Drain, cover and set aside.
Melt the butter in a medium saucepan; add the flour, stirring well with a wire whisk. Gradually add the milk and wine, stirring until smooth. Add the lemon zest, dill, salt, pepper and garlic. Cook over medium heat 8 minutes or until thickened and bubbly, stirring constantly.
Combine the pasta, shrimp and sauce. Sprinkle with green onions and serve immediately.