Here is what I found until now. I'm using JBoss App Server 4.2.3 GA with it's original version of jboss remoting. One specific change I did to the remoting configuration was to add idleTimeout parameter with value 120 seconds. So from here start my problems. Without this timeout all will be fine. When it is specified the IdleTimer will close sockets for all inactive ServerThread instances including those that current are busy processing some request. (In SocketServerInvoker.java the problem comes from calls like this: svrThread.unblock();) When such socket is closed on the sever the client side sends another instance of the same request(invocation) and as result I get an exception for the second request (Application Error: no concurrent calls on stateful beans). In the initial thread I get exception that Transaction status is ABORTING. All these findings are valid for all versions of JBoss Remoting 2.2.2. For 2.4 I see that all calls to shutdown and unblock method are commented and replaced just with call to shutdown later in the code. Regarding UserTransaction timeouts there is still problem. At least I can't find anything in the code that will respect the value for user transaction timeout. They will work only if their timeout is less then the timeout value specified in jboss-service.xml. Doychin View the original post : http://www.jboss.org/index.html?module=bb&op=viewtopic&p=4211834#... Reply to the post : http://www.jboss.org/index.html?module=bb&op=posting&mode=reply&a...