Yes it is possible but will depend on which cabin on which ship. Did you have a particilar one in mind? If you do. the website for that cruiseline will have a section on each ship that will describe bed configurations within the descriptions of the cabins.section If you are trying to find a suitable ship, then either call thie specialists on this website or use the Berlitz guide section to help you find what you are looking fo.
Yes it is possible, usually the config is 2 lower berths and 1 upper pullman bed [that pulls out from the ceiling or the wall each night.