code: public void prependMessage(String message) {
          if (iMessage == null) {
              iMessage = message;
          } else if (message != null) {
              iMessage = message + ": " + iMessage;
          }
      }
docs: Provide additional detail by prepending a message to the existing message.
  A colon is separator is automatically inserted between the messages.
  @since 1.3