Hello Ed, I don't know why but I thought that StaleObjectStateExceptions are errors. But in docs (chapter 6.5) and in JIRA http://jira.jboss.com/jira/browse/JBPM-995 is clearly written that StaleObjectStateExceptions are expected behaviour and it doesn't matter if these exceptions occur. Now I have tried to hide those excetions, unfortunately I had problems with that. I was able to hide them only with changes to source code. See http://www.jboss.com/index.html?module=bb&op=viewtopic&t=137456, I think that it is bug in jBPM. Not all StalebjectStateExcetions are hidden. I hope that all my "problems" were caused by StaleObjectStateExceptions that are not errors, I can ignore those exceptions. I have some block in my mind against those exception. When I am finished with my process I will report whether it works in cluster. Thank all for help and sorry for perplexes. Regards Pavel View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=4158357#... Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&a...