The winners of the Thomond Park clash will play the winners from the game played the previous evening between Leinster and Glasgow.
Shannon are scheduled to play their AIB League semi-final against Clontarf that same weekend.
1) Neath Swansea Ospreys v Ulster - Sat 30th April, kick-off 17.30.
(2) Munster v Edinburgh Rugby - Sat 30th April, kick-off 19.30.
(3) Leinster v Glasgow Rugby - Fri 29th April, kick-off 19.30.
(4) Newport Gwent Dragons v Llanelli Scarlets - Fri 29th April, kick-off 19.05.