复制一份JBOSS_HOME\docs\examples\jca\mysql-service.xml到
JBOSS_HOME\server\all\deploy,
然后修改standardjbosscmp-jdbc.xml中的      <datasource>java:/DefaultDS</datasource>
      <datasource-mapping>Hypersonic SQL</datasource-mapping>改为      <datasource>java:/MySqlDS</datasource>
      <datasource-mapping>mySQL</datasource-mapping>