I ran the icefaces3basic.war and can reproduce the "Session Expired" issue. I can also verify that the problem is caused by the ViewState problem noted and fixed in the JIRA from our system: http://jira.icesoft.org/browse/ICE-8149. If I interpret the results of your testing accurately, it would appear that a regression was introduced in between the release of the open source version of ICEfaces 3.0.0 and ICEfaces EE 3.0.0 which is causing the behaviour. The fix has been applied to the upcoming release (3.1.0) as well as the 3.0.x maintenance branch so will be in the next EE patch release (EE-3.0.0.GA_P01) as well. If you are an EE customer and you need a solution sooner than that, you should go through the ICEfaces Product Support channels to discuss the options.