1. Mix the Jello powder with the crushed pineapple and it's juice in a small saucepan.
2. Drain the juice from the oranges, and add to the saucepan.
3. Bring to a boil and remove from the heat to cool.
4. Once cooled, put in a large mixing bowl.
5. Add the buttermilk and mix well.
6. Fold in the cool whip and pecans.
7. Pour into a Jello mold, or bowl.
8. Chill in the refrigerator at least 3 hours, or until set.