We all have a different version! It's amazing how these things change over time....the one I learnt was:
A sol, a sol, a soldier's life for me,
Two pis, two pis, two pistols on my knee,
For cu, for cu, for curiosity
To fight for the old cunt, fight for the old cunt, fight for the old country!

It always had me in stitches as a kid... :)