Ratzinger Joke

[Now I got this joke off the Catholic Pages website , so don't anybody go getting all offended. Since it still refers to him as Cardinal I'm thinking it's an old one.]

Karl Rahner, Hans Kung and Joseph Cardinal Ratzinger all die on the same day, and go to meet St. Peter to know their fate.
St. Peter approaches the three of them, and tells them that he will interview each of them to discuss their views on various issues.
He then points at Rahner and says "Karl! In my office..." After 4 hours, the door opens, and Rahner comes stumbling out of St. Peter's office. He is highly distraught, and is mumbling things like "Oh God, that was the hardest thing I've ever done! How could I have been so wrong! So sorry...never knew..." He stumbles off into Heaven, a testament to the mercy of Our God.
St. Peter follows him out, and sticks his finger in Kung's direction and "Hans! You're next..." After 8 hours, the door opens, and Kung comes out, barely able to stand. He is near collapse with weakness and a crushed spirit. He , too, is mumbling things like "Oh God, that was the hardest thing I've ever done! How could I have been so wrong! So sorry...never knew..." He stumbles off into Heaven, a testament to the mercy of Our God.
Lastly, St. Peter, emerging from his office, says to Cardinal Ratzinger, "Joseph, your turn." TWELVE HOURS LATER, St. Peter stumbles out the door, apparently exhausted, saying "Oh God, that's the hardest thing I've ever done..."