In a medium sauce pan coated with nonstick vegetable spray, saute green onions over medium heat until transparent. Add water if necessary to prevent sticking. Mix milk with flour and add to onions. Bring to a boil stirring constantly. Cook for 5 minutes or until mixture starts to thicken. Add reserved clam juice, potato, corn, thyme, bay leaf and cayenne pepper. Cover, reduce heat; simmer 15 minutes or until potatoes are tender. Remove bayleaf and discard. Stir in clams and heat through. Salt and pepper to taste.