I have the logs. They don't show anything helpful, at least not right around the time of the failure, which is in the server2 log at 17:04:09,119. They do show this test server2 was started about 50 times before this failure occurred. So, it seems quite intermittent and likely hard to track down. A key thing is understanding what exactly changed that triggered this, or if we don't really know, understanding we don't really know so we can avoid chasing the wrong thing. So, 1) Did this failure start appearing regularly after a certain point? Or did it just happen once? 2) If it's regular, was the change to the stack config the *only* change before it started happening? 3) When did you start testing with JGroups 2.6.5? How much testing did you do with JGroups 2.6.5 before this issue appeared? anonymous wrote : I will not hold the JBM 1 release because of this, but I will open a JIRA on JBAS for this issue. +1. The only thing happening when this failed was an ordinary start of a server. Your tests failed because the server didn't start properly. The AS testsuite starts servers all the time; it's perfectly reasonably to track this issue there. However, if you think the problem will consistently appear over the course of a testsuite run, I make ask for some help in running your testsuite occasionally, to see if changing settings makes the issue go away. View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=4187566#... Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&a...