Eamonn Carr was the Drummer in the HorseSlips, while Barry Devlin and Charles O'Connor shared the lead vocals. They in fact never released "Whiskey in the jar" on any of their albums but as all Irish Trad bands, most likely played it live at gigs.
The Dubliners were the band who threw the song to the fore front in the mid 60's.
It was again taken on by Thin Lizzy front man Phil Lynott in the early 70's and rehashed in to classic rock version. During all this time it was and is regularly played by many an Irish band. In the early 90's, Metallica took the song a step further from where Phil Lynott left off 20 years or so earlier and made a much heavier and powerful rendition. It remains a long time, and deserved, Irish Trad classic.
For more info, see below links:
http://en.wikipedia.org/wiki/Whiskey_in_the_Jar
http://www.horslips.ie/