From Mark Chopper Read’s autobiography, One Thing Led To Another:
“One time, Jimmy Loughnan and I tried to break out of B Division [at Pentridge Gaol]. We were up in the ceiling above the B Division library, had lollies and cordial and were set to go. But, even before we got out of the place, Jimmy had eaten all the lollies and drunk all the cordial, and so he needed to have a widdle. He widdled into his coat but some of the urine went down the wall […] and we were discovered.
“But I’ve learned recently that that failed escape attempt might have been the reason that Bon Scott from AC/DC wrote the song ‘Jailbreak’.
“When I think about it, that could be true because I once met Bon Scott at the Southside Six Hotel. This was a place I used to go to watch live music in Melbourne. Remember Kush, with Jeff Duff as the lead singer? Yeah, you’re old, aren’t you?
“Jeff Duff had a deep voice but there wasn’t much else that was manly about him. He was a pretty flamboyant sort of character. He used to get around on stage dressed in a mink stole and fishnet stockings, and stuff like that. His first album, in 1975, was Snow White and the Eight Straights.
“Well, anyway, at the Southside Six, Jeff Duff introduced me to Bon Scott. I didn’t think a real lot of it at the time, as I used to get introduced to a lot of musicians back then.
“But it would be kind of interesting if Bon Scott had remembered me from that night, heard the story of Jimmy and me trying to get out of prison, and wrote ‘Jailbreak’ for us. It would be a nice way for me and Jimmy to be remembered.”
The book is here via Google