Well it's Booking->Days->BookingResources i.e. Booking -> (List of Days) -> (List of Booking Resource) as Set is not well supported! This is shown as a datatable within a datatable in the Richfaces UI... Anyhow the BookingResources (Discriminated Entities) can, given the right Resource Type, have Riders which is mapped to a rich:spinner The bug was that the spinner only raised events when something came after it in the list... as I said too weired for me to track down so done another way. .. Lists of Lists rendered as nested datatables do actually give Richfaces a few problems. Should be fun when I go one more level deep to the actual list of riders for each Resource... ;) View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=4125735#... Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&a...