select profile,resource_name,limit from dba_profiles where resource_name='PASSWORD_LIFE_TIME';
ALTER PROFILE DEFAULT LIMIT PASSWORD_LIFE_TIME UNLIMITED;
select profile,limit from dba_profiles where resource_name='PASSWORD_LIFE_TIME';

alter user 用户名 identified by <原来的密码> account unlock;

参考：http://www.cnblogs.com/luckly-hf/p/3828573.html