SQL QUERY - Mailing list pgsql-sql

CREATE FUNCTION public.auto_incremento() RETURNS trigger AS '
begin
new.id = (select (max(id) + 1) from teste);
return new;
end;' LANGUAGE 'plpgsql'

I created a trigger that uses this function, but i want to the function be usefull for all tables and not only to tbale teste.

Someone know how ???

Pedro Igor