CATSEARCH wildcard % does not work

Hi,
I tried to use wildcard % in catsearch, however it seems that it does not work.
According to document http://g-solutions.net/icreate-content/main/oracle_wildcard_searching.aspx, wild card % is allowed CATSEARCH.

********************************************************************************************
SELECT id, price, name
FROM   my_items
WHERE  CATSEARCH(description, '%ouse%', null)> 0;

no rows selected

********************************************************************************************
SELECT id, price, name
FROM   my_items
WHERE  CATSEARCH(description, 'House', null)> 0;

      2860        859
House: 859


        ID      PRICE
---------- ----------
NAME
----------------------------------

      2861        860
House: 860

      2862        861
House: 861

      2863        862
House: 862


        ID      PRICE
---------- ----------
NAME
----------------------------------

      2864        863
House: 863


1000 rows selected.
**********************************************
Am I missing any configuration ? Please guide.

Regards,
Eye Gee