Alessio -- Thanks for getting back to me. I'm sure I don't have the JBossws JARs in my EAR (that's why it can't find ProviderImpl). I'll search my classpath to see where that javax.xml.ws.spi.Provider is being looked up from. I'm afraid JBossWS-native might still be installed in the server classpath even though I did install jbossws-metro using the Ant build. I'll see if I can't track that down. Is there any way to "query" the classpath for a given resource to find out what JAR it's coming from? :) Thanks again. View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=4184634#... Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&a...