求mysql5.1 定时任务

现有mysql5.1数据库表casual_user：
SQL code

CREATE TABLE `casual_user` (
`id`  int(11) NOT NULL AUTO_INCREMENT ,
`username`  varchar(20) CHARACTER SET utf8 COLLATE utf8_general_ci NULL DEFAULT NULL ,
`verification`  varchar(50) CHARACTER SET utf8 COLLATE utf8_general_ci NULL DEFAULT NULL ,
`del`  varchar(2) CHARACTER SET utf8 COLLATE utf8_general_ci NULL DEFAULT NULL ,
`time`  datetime NULL DEFAULT NULL ,
PRIMARY KEY (`id`)
)

需要在每天晚上00点整的时候删除表中del为‘T’，time为一星期前的数据，请问大侠们怎么写sql语句~~

set global event_scheduler = 1;
DELIMITER $$

CREATE EVENT `FF` ON SCHEDULE EVERY 1 DAY STARTS '2011-05-31 22:00:00' ON COMPLETION NOT PRESERVE ENABLE DO BEGIN
delete from `casual_user` where del='T' and week(time)=week(now())-1;
END$$

DELIMITER ;

CREATE EVENT `myEvent1` ON SCHEDULE EVERY 1 DAY STARTS '2011-05-31 00:00:00' 
DO 
DELETE FROM `casual_user` WHERE del='T' AND `time` < curdate() - interval 7 days;