Yep, the "Jack-Ass Song" seems to be "Jackass Jump An' Bray" given a different name.Swedish webpage with lyrics for Belafonte songs . Certainly sounds like a more plausible candidate for the inspiration of "Tie Me Kangaroo Down" - it actually has the line Suibhne Astray quoted- " Don't tie me donkey down there". Is it possible Rolf Harris actually misremembered the song he heard? Both songs have the theme of an unusual and unruly donkey and use directions as part of the chorus- "hold him" and "don't tie him down there".