I had this same thing just happen to me a week ago. The PTO rod is sticking through the front of the case/jug and the bottom part of the jug and top part of the case are in pieces in the belly pan. The rod does not have the hole on top for the wrist pin, it has been completely sheared off.
This is also on an 04 800, which has been an 840 for the last 300 miles. I haven't torn it down to see what the rest of the story is.
