Simmer water, bulgur and lamb together for 2 to 3 hours. Remove meat and bones, and skim off fat. Add carrots, onions or leeks, celery, parsley, salt, pepper, and curry powder. Cover and continue cooking until vegetables are tender. Remove all meat from bones, dice, and return to soup mixture. Blend butter or margarine and flour together over low heat; stir into 2 cups of soup mixture, then stir into remaining mixture. Continue cooking until soup is thickened (about 3 minutes). Adjust seasoning to taste.