No problem, it can be quite confusing at times. It's because the rugby team represents the whole island of Ireland. Amhran na bhFiann was deemed inappropriate because it is the official national anthem of the Republic of Ireland and because of the Nationalist theme of it. I have to say though, I do like Ireland's Call, especially when you are in the middle of the crowd watching the match!
Oh and the guy who wrote it lives across the road from me.