Preheat oven to 325 degrees F.

Melt the butter in a skillet over medium heat.  Add the bell pepper, onion, and celery and saute for 2 minutes.  In a bowl, combine the soup, mayonnaise, parmesan, crabmeat, shrimp, and pepper.  Stir the sauteed vegetables into the seafood mixture and spoon this mixture into a lightly greased 8 by 11-inch casserole dish.  Bake for 30 minutes.  Serve with toast points or crackers.