Whiskey in the Jar

"Whiskey in the Jar" is one song I really love. I first heard the version by Metallica, rather saw the video. Later I heard the Thin Lizzy version of it and was blown away. Awesome.
But the fact is, its actually an Irish Folk song, which is also pretty good.
Versions by both Metallica and Thin Lizzy are different from the original. Thin Lizzy replacing "Jenny" by "Molly" and so on.