Trigger Help on 8.0

I have a trigger that compiles fine on ORACLE 7.3. I know try to migrate the code to 8.0.5 and it doesn't compile.

Here's the source:

create trigger agent_timestamp
before insert or update on agent
for each row
declare
 operuser varchar2(15);
begin
select osuser into operuser from v$session where audsid=userenv('sessionid');
:new.revised_date := sysdate;
:new.revisor := upper(operuser);

end;

Why doesn't this work on ORACLE 8.0? Received on Mon Jan 11 1999 - 16:37:17 CST