The oracle Stored procedure problem

hi all,
   I encountered a problem.
The table structure is as follows:
create table express_info
(
  exp_num char(10) not null,
  ori_station char(8),
  dest_station char(8),
  consignee char(8),
  shipping_address char(50),
  qty number,
  constraint pk_exp primary key(exp_num)
)
--------------------------------------------
create or replace procedure update_traninfo
( en char,
  os char,
  ds char,
  ce char,
  sa char,
  qy numer
)
is
begin
update express_info set ori_station=os,dest_station=ds,
  consignee=ce,shipping_address=sa,
  qty=qy
  where exp_num=en;
end update_traninfo;
---------------------------------------
The above SQL statement can successfully compile and build a successful.
but,Error when the execution,The error message is as follows:
invalid SQL statement.
now,I just want to know the syntax of the stored procedure Existence problem?

thanks in advance.