title: Hashmap (of strings) in grails domain Class
body: <p>Currently I have a Grails domain class with a HashMap of strings (HashMap metadata = new HashMap().</p>
  
  <p>Everything is working fine with database persistence on creation (stored as  BLOB by the way), start-up, shutdown, etc...</p>
  
  <p>I have a nasty feeling that this is not okay for some reason, if that is the case why?  if not, then never mind.</p>
  
  <p>Versions etc Grails 2.0, Groovy 1.8, Java 1.6, Tomcat 6 MySQL 5.latest</p>