In this case the removeTargetGroup parameter turns out to be NULL: <h:dataTable value="#{project.targetGroups}"var="targetGroup"> | <h:column> | <s:button value="#{targetGroup.name}" action="#{projectManager.removeTargetGroup(targetGroup)}"/> | </h:column> | </h:dataTable> | But in this case it is as it should be: <h:dataTable value="#{project.targetGroups}"var="targetGroup"> | <h:column> | <s:button value="#{targetGroup.name}" action="#{projectManager.removeTargetGroup(project.targetGroups[0])}"/> | </h:column> | </h:dataTable> In both cases - targetGroup.name displays as it should. How can it be that the action method parameter is NULL in the first case? Is it a configuration issue? regards, Peter View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=4026281#... Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&a...