Date Timezone Oracle PLSQL

SQL>
SQL>
SQL>  column current_timestamp format a38
SQL>  select current_timestamp from dual;
CURRENT_TIMESTAMP
--------------------------------------
16-JUN-08 04.27.20.203000 PM -08:00
1 row selected.
SQL>  select current_timestamp + numtodsinterval( 2, 'hour' ) current_timestamp from dual;
CURRENT_TIMESTAMP
--------------------------------------
16-JUN-08 06.27.20.284000000 PM -08:00
1 row selected.
SQL>
SQL> --