In a medium saucepan combine rhubarb, sugar, raisins, lemon peel and juice, orange peel and juice, water (omit water if using frozen rhubarb), and salt. Bring to boiling; reduce heat. Boil gently, uncovered, about 30 minutes or until mixture has thickened (should have about 1-3/4 cups). Transfer to a bowl.
Cover and chill in the refrigerator about 2 hours or until completely cool. Stir in nuts. Serve with cheese and shortbread cookies. Cover and store in refrigerator up to 2 weeks or freeze in freezer container up to 2 months. Makes about 2 cups.