According to the release notes no confiugration changes should be needed if the jdk6 version was downloaded but it also suggests one other thing. anonymous wrote : The other option is to download the jdk6 distribution (jboss-5.0.0.GA-jdk6.zip) in which case no configuration changes are required. If you still have problems using JBoss with a Sun Java 6 runtime, you may want to set -Dsun.lang.ClassLoader.allowArraySyntax=true, as described in http://jira.jboss.com/jira/browse/JBAS-4491. Also make sure jaxb-api.jar is in the endorsed folder as well. Might I suggest temporarily deleting the other copies of the jar files, which are usually in the jboss/client folder and jboss/lib, just to see if this is the problem. jar files: jaxb-api.jar jbossws-native-saaj.jar jbossws-native-jaxrpc.jar jbossws-native-jaxws.jar jbossws-native-jaxws-ext.jar [/url] View the original post : http://www.jboss.org/index.html?module=bb&op=viewtopic&p=4245397#... Reply to the post : http://www.jboss.org/index.html?module=bb&op=posting&mode=reply&a...