Marinate pork with soy sauce and salt for 1 hour. In a large saucepan, place pork, marinade, ginger, garlic, onion, turmeric, oil, shrimp paste, chili flakes and 1 cup water. Mix well, Bring to boil over moderate heat. Cover and cook for 40 minutes. Add remaining water and pumpkin. Cook 15 minutes or until the pork is tender and most liquid evaporated. Serve warm over white rice.