From my experience with 3.2.3 and 4.0.2 that normally happens when you have another application, not necessarily JVM, running on port 1099. If you are running on windows, you could probably see if that is true by running netstat on the command console. Again from my experience, if you are running this from a development box and you also have some IMs installed on to it as well, the IMs may be the cause of the error. Try closing all IMs then run Jboss.