Please, first of all check this cases(most of all 3 and 4, may be you need to use int instead of long): A problem occurred accessing a property of an instance of a persistent class by reflection, or via CGLIB. There are a number of possible underlying causes, including * failure of a security check * an exception occurring inside the getter or setter method * a nullable database column was mapped to a primitive-type property * the Hibernate type was not castable to the property type (or vice-versa) http://www.hibernate.org/hib_docs/v3/api/org/hibernate/PropertyAccessExce... View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=4193313#... Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&a...