Can't grant execute to user, even as SYS?

[DrNeko]

Hello,
I have a user that has created a stored procedure. However, I'm having difficulty granting the execute privilege to any user. I even executed the following statement as SYSTEM and SYS (as SYSDBA) where tim is the user that created the stored procedure and cs_pass is the stored procedure:

SQL> grant execute on tim.cs_pass to toby;
grant execute on tim.cs_pass to toby;
                     *
ERROR at line 1:
ORA-01031: insufficient privileges

I also granted to following to myself, and I still get the same result. Any help?

GRANT DBA TO SYSTEM;
GRANT CONNECT TO SYSTEM;
GRANT RESOURCE TO SYSTEM;
GRANT ANY PRIVILEGE TO SYSTEM;
GRANT CONNECT_MTN TO SYSTEM;
GRANT EXP_FULL_DATABASE TO SYSTEM;
GRANT IMP_FULL_DATABASE TO SYSTEM;
GRANT SELECT_CATALOG_ROLE TO SYSTEM;
GRANT EXECUTE_CATALOG_ROLE TO SYSTEM;
GRANT AQ_ADMINISTRATOR_ROLE TO SYSTEM;
GRANT GATHER_SYSTEM_STATISTICS TO SYSTEM;
ALTER USER SYSTEM DEFAULT ROLE ALL;
GRANT ANALYZE ANY TO SYSTEM;
GRANT ALTER ANY TYPE TO SYSTEM;
GRANT ALTER ANY INDEX TO SYSTEM;
GRANT ALTER ANY TABLE TO SYSTEM;
GRANT EXECUTE ANY TYPE TO SYSTEM;
GRANT SELECT ANY TABLE TO SYSTEM;
GRANT ALTER ANY INDEXTYPE TO SYSTEM;
GRANT ALTER ANY PROCEDURE TO SYSTEM;
GRANT DEBUG ANY PROCEDURE TO SYSTEM;
GRANT UNLIMITED TABLESPACE TO SYSTEM;
GRANT EXECUTE ANY INDEXTYPE TO SYSTEM;
GRANT EXECUTE ANY PROCEDURE TO SYSTEM;
GRANT SELECT ANY DICTIONARY TO SYSTEM;

It it helps, the code for the stored procedure is:

CREATE OR REPLACE PROCEDURE cs_pass
	(usernam varchar2,
	 passw varchar2)
	AUTHID DEFINER IS

  usern     varchar2 (10);
  pw        varchar2 (10);
  sb	    char     (2);
  oper      char     (8);
  comp	    char     (10);
  user      char     (10);
  user_id   numeric  (5);
  fail_sw   char     (1);

PROCEDURE write_log (comp char, user char, user_id numeric, fail_sw char, oper char) IS

BEGIN
execute immediate 'INSERT INTO TIM.T_CS_PASSWORD_LOG (comp, TIM_username, TIM_user_id,
		success_switch, operation, create_date) values (:1, :2, :3, :4, :5, :6)'
                using comp, user, user_id, fail_sw, oper, sysdate;
END;

BEGIN

fail_sw := 'F';
comp    := usernam;
user_id := uid;
oper    := 'PASSWORD';

  execute immediate 'SELECT USERNAME FROM DBA_USERS WHERE USER_ID = :1' INTO user USING uid;

usern   := usernam;
pw      := passw;
sb      := substr(usern, 1, 2);

 if sb <> 'BK' then
     write_log(comp, user, user_id, fail_sw, oper);
     return;
 end if;

 if upper(pw) = 'UNLOCK' then
     execute immediate 'alter user '||usern||' account unlock';
     oper := 'UNLOCK  ';
     fail_sw := 'S';
     write_log(comp, user, user_id, fail_sw, oper);
     return;
 end if;

     execute immediate 'alter user '||usern||' identified by '||pw;
     fail_sw := 'S';
     write_log(comp, user, user_id, fail_sw, oper);
  RETURN;
END;
/