The Dispatch seems to be an important JAXWS client construct. It does not provide everything that any JBossWS user needs. Hence there are chances where he may have to cast the dispatch to ConfigProvider and provide the additional settings as outlined in the forum thread.
For this reason, I suggest adding a properties file on the classpath and one setting that can be done via system property. The DispatchImpl implementation needs to handle this one system prop and use the associated properties file to get the settings.