more trouble with triggers/functions

hello.

a quick note - i have not recieved a single [GENERAL] post since friday,
9/29.  is anyone else having this problem or just me?

on to my question...i have been trying to create a trigger or
trigger/function combination but i have so far been unsuccessful.  my task
is simple, when someone inserts a row in the PERSON table, create a row in
the RESOURCE table (note that i have to pass parameters).  details below...

first, the basic procedure and trigger are shown here:

CREATE FUNCTION sp_person_resource() RETURNS bool
    AS 'insert into resource(rid, name, type, desc) values (1905, ''chris'',
''person'', ''blah''); select true;'
    LANGUAGE 'sql';

CREATE TRIGGER trig_person_resource BEFORE INSERT ON person
    FOR EACH ROW EXECUTE PROCEDURE sp_person_resource();

i do not know what to use for a return type (i don't really need to return
anything).  but when i try to write a trigger to call that fn, it tells me
that the fn must return opaque...i modify my proc but it tells me that "sql
fns cannot return type opaque."

what's going on?  what is opaque?

thanks
chris