I also encountered this problem: The docs neglect to tell you that you also need to comment out the reference above the MBean declaration <!-- When using in-process (standalone) mode --> <!-- jboss:service=Hypersonic,database=localDB --> <!-- Uncomment when using hsqldb in server mode --> jboss:service=Hypersonic Did that as well and it all worked fine View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=3957324#... Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&a...