The first refrain line in the Irish song is "O my blackbird gay" - "'S oro londubh bui", where 'bui' literally means 'yellow'. An Irish-language forum suggests that Stephens mistranslated "londubh" (blackbird) as "leann dubh" (black beer); presumably he then dealt with the "bui" by inserting an 'and' that wasn't there. I can't bring myself to mind very much, either about that or about the bits he cut out in translation - it's such a fine song.

Apparently James Joyce shared a birthday with James Stephens and once sang the song to Stephens at a joint birthday party. He's said to have had a lovely voice.