1. Cut the lobster rail and claw meat into 1-inch pieces; refrigerate. Coarsely chop the shells. In a large saucepan, combine the shells with the water, leeks, carrots, celery, parsley, garlic, 1 teaspoon of salt and 1/2 teaspoon of pepper. Bring to a boil, then simmer over moderate heat until reduced to 3 cups, about 40 minutes.
2. Strain the lobster broth into a medium saucepan. Add the Napa cabbage and lobster meat and bring to a boil. Simmer over moderately low heat until the cabbage is tender, about 5 minutes. Stir in the lobster coral and season with salt and pepper.
3. Meanwhile, cook the ravioli in a large pot of boiling salted water until al dente, about 10 minutes; drain. Arrange the ravioli in soup plates and ladle the lobster and cabbage broth on top. Sprinkle with chives and serve.
Heart-shaped lobster ravioli can be ordered until February 9 from the Ravioli Store, 212-925-1737.