Never mind, guys, I found the problem. My mistake. My fault was that the data table with the selectBooleanCheckboxes weren't inside the form brackets. So when I got the wrong result back from JSF, I was kind of mislead. Instead of getting your data back unchanged, by default you're getting "false" aka "unselected" for all checkboxes. If I place the checkboxes properly in the form, everything works fine. However, the original question remains: is there a way to debug such a problem? In this case I helped myself by writing a "LoggerMap extends HashMap" and passed that one to JSF. But that's an awful lot of work if you need to supply custom "debugger" classes like this for all of your debugging problems. Right now it looks to me like debugging your JSF stuff is a bit like programming in the early 80s - log everything by hand in what you could be interested in, and continue until you found what's going wrong. Kind of unproductive nowadays. Well, the good news for me is that I was finally able to locate the problem. But it's consuming time. 2 weekends for 2 problems - by far too much. View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=3960250#... Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&a...