Preheat oven to 350°.
In large mixing bowl, on low speed, combine cake mix, 1 egg, butter and 2 teaspoons pumpkin pie spice until crumbly. Press onto bottom of 15x10 inch jellyroll pan. In large mixing bowl, beat cheese until fluffy. Gradually beat in sweetened condensed milk, then remaining 2 eggs, pumpkin, remaining 2 teaspoons pumpkin pie spice and salt; mix well. Pour over crust; sprinkle with nuts. Bake 30 to 35 minutes or until set. Cool. Chill; cut into bars. Store covered in refrigerator.