public RelationDescription getRelationDescription(String entityName, String propertyName) {
   final EntityConfiguration entCfg;
   if (isVersioned(entityName)) {
     entCfg = get(entityName);
   } else {
     entCfg = getNotVersionEntityConfiguration(entityName);
   }
   final RelationDescription relDesc = entCfg.getRelationDescription(propertyName);
   if (relDesc != null) {
     return relDesc;
   } else if (entCfg.getParentEntityName() != null) {
     // The field may be declared in a superclass ...
     return getRelationDescription(entCfg.getParentEntityName(), propertyName);
   } else {
     return null;
   }
 }