Preheat oven to 500 degrees F (260 degrees C). In a small bowl, combine the milk and salt. In a separate bowl, mix together the bread crumbs, Parmesan cheese, and thyme. Dip the haddock fillets in the milk, then press into the crumb mixture to coat. Place haddock fillets in a glass baking dish, and drizzle with melted butter. Bake on the top rack of the preheated oven until the fish flakes easily, about 15 minutes.