change CREATE_TABLES_ON_STARTUP = FALSE in rhq-jdbc2-service.xml and rhq-jdbc-state-service.xml files http://www.jboss.org/index.html?module=bb&op=viewtopic&p=4227322#4227322
this already looks fixed in trunk. I just checked all the files and that flag is FALSE in all of them.
This bug was previously known as http://jira.rhq-project.org/browse/RHQ-2041