docs: public Object[] getForeignKeyValues(Object obj, ClassDescriptor mif)
              throws PersistenceBrokerException
      {
          FieldDescriptor[] fks = getForeignKeyFieldDescriptors(mif);
          // materialize object only if FK fields are declared
          if(fks.length > 0) obj = ProxyHelper.getRealObject(obj);
          Object[] result = new Object[fks.length];
          for (int i = 0; i < result.length; i++)
          {
              FieldDescriptor fmd = fks[i];
              PersistentField f = fmd.getPersistentField();
  
              // BRJ: do NOT convert.
              // conversion is done when binding the sql-statement
              //
              // FieldConversion fc = fmd.getFieldConversion();
              // Object val = fc.javaToSql(f.get(obj));
  
              result[i] = f.get(obj);
          }
          return result;
      }