Bump! Am I really the only one who is using MySQL? Or, asked in an other way: Is anyone using MySQL 5.0.x together with JBoss 4.2.0 GA without getting this warning? If so, please post your datasource configuration. @JBoss Devs: *PLEASE* have a look at this! I spend the last days looking for a solution but found nothing - except the JIRA issue mentioned in my first post. If I don't get a response I'll open a new issue but I really don't think that I'm the only one who's using MySQL?! Again: To repoduce this just replace /server/default/deploy/hsqldb-ds.xml with /docs/examples/jca/mysql-ds.xml, adapt it to your configuration, startup the server and you will see this exception (even with a clean installation and NO applications installed). Last but not least it's probably worth mentioning that the connection is working because the necessary tables get created but I'm still worried why this is happening! View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=4049661#... Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&a...