There are several "Wexford Carols". the one listed by Colm is usually called the "Enniscorthy Carol". It was collected by a man clled Grattan Flood a the turn of the century. Details are in the Oxford Book of Carols - at least in the 1920's edition I have!
Thaere is a peculiar tradition of carol-singing in a Wexford village called Kilmnore Quay - but this is not one of theirs.
See the Voice Squad albums for this and others. Best Wishes