the selects are pretty normal, it's the JobExecutor doing its work and polling the database for new jobs...
someone else had a similar classloading problem some time ago:
http://community.jboss.org/message/538997
In case this is really a classloading issue:
Tomcat has a feature that serializes and saves session data and maybe other stuff between restart, you can turn that off by
setting:
<Manager pathname="" />
in tomcat's context.xml, maybe this is worth a try...