Please report it in JIRA. Workaround is to delete seam-gen/build.properties when switching to MySQL. View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=4015578#4015578 Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&p=4015578