Thaw wrappers if frozen, covering with damp towel to prevent drying out.
Peel, devein and chop prawns. Place shells in pot with 4 cups of water with 1/2 tsp salt and boil until reduced to 2 cups.
Saute chicken, pork, potatoes, celery, carrots, snow peas and seasonings. Cook until done. Add garlic, prawns and 1 cup of prawn stock, and continue to cook until prawns are pink. Strain if necessary and set aside to cool..
Scoop 1 tbsp of mixture into a corner of the wrapper, and fold in left and right corners. Moisten ends with water to hold. Freeze.
Deep fry frozen lumpia until golden brown. Serve with Banana Ketchup (available in Asian markets) or Dipping Sauce.