I just gave the title as I found it,and hadn't even thought about that, but I see your point.  The lyric I linked to above has Buachaill ón Éireann in the verse.  I don't know why the title should be different; the only reference I could find to Buachaill ón Éireann was to a song partly based on it on a Van Morrison record.  There are other references on the web, all apparantly to Buachaill ón Éirne; there is another set of the text here, with an additional verse but no translation:  Buachaill ón Éirne:  I'd have guessed that the confusion arose with Clannad, but Richard Robinson (one of the 2 entries at JC) also has it spelled that way, and I doubt if they were his source.  Perhaps somebody can shed some light on this for us?

Malcolm