I've got it ... a not very inspired version with Paul on vocals (John sings the very last words of the take of mine).
It was recorded during the Great Back Sessions (Sunday, January 26th, 1969 at Apple Studio -with Billy Preston-). Runtime: 2:18, tho mine: 1:28. Surely the rest is only chat.
If you want to know some more, well, you know where I am.
P.S. Bootlegforum is a good place for this kind of things, do you know what I mean?
http://dmbeatles.com/cgi-bin/Blah/Blah.pl?b-conversations/m-1133830115/