docs: public void addBookmarkFilter(Object bookmark)
      {
          if (m_recordMessageFilter != null)
          {
              if (bookmark == null)   // Never
                  bookmark = NO_BOOKMARK;
              Hashtable<String,Object> properties = new Hashtable<String,Object>();
              properties.put(GridRecordMessageFilter.ADD_BOOKMARK, bookmark);
              m_recordMessageFilter.updateFilterMap(properties);
          }
      }