SQL & PL/SQL

Hi


How do I convert the EST time zone to GMT zone, and want to have the day light saving adjusted automatically .
Is new_time will take care of day light saving change?

Tried from_tz, but that is not getting the correct GMT time .


SELECT FROM_TZ(CAST(TO_DATE(sysdate, 'dd/mm/yyyy HH24:MI:SS') AS TIMESTAMP), 'US/Eastern') AT TIME ZONE 'GMT' From_TZGmtTime ,
to_char(new_time(sysdate,'EST','GMT'),'dd-mon-yyyy hh24:mi:ss') New_TimeGmtTime,
To_char(sysdate,'dd-mon-yyyy hh24:mi:ss') EST_LocalTime
FROM DUAL ;

FROM_TZGMTTIME
_______________________________
06-JUL-11 04.56.00.000000000 AM GMT


NEW_TIMEGMTTIME
___________________
06-jul-2011 17:23:55


EST_LOCALTIME
_______________________
06-jul-2011 12:23:55


Both From_Tz and New_Time is not giving me the correct GMt time , the current GMT time when i am running this query is 16:23

Thanks

Ben