I'm no expert but in src\java.jbpm.test\org\jbpm\context\exe\VariableQueryDbTest.java there is an example of a query to another type of value. Granted it does not use org.jbpm.context.exe.VariableInstance but org.jbpm.context.exe.variableinstance.XXX directly which is probably not what you are hoping for. Jbpm has quite some code to handle the mapping of variables. I guess that's not a good sign. Maybe in a hibernate specific forum you'll have better luck. Regards, Johan View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=4064035#... Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&a...