Accessing serials through rules

With rules, I can allow people to insert into a table that they don't
otherwise have access to.  And default values seem to get inserted fine
except when the field is type serial (and the default is from a
sequence).  Then you get write permission errors on the associated
sequence.  Should it be like this?

Example:

CREATE TABLE mine (
  id serial,
  pub integer,
  priv integer
);
CREATE VIEW ours AS SELECT id, pub FROM mine;
CREATE RULE ours_ins AS ON INSERT TO ours DO INSTEAD
  INSERT INTO mine (pub) VALUES (NEW.pub);
GRANT ALL ON ours TO public;

Now connect as someone else...

INSERT INTO ours (pub) VALUES (1);
ERROR:  mine_id_seq.nextval: you don't have permissions to set sequence
mine_id_seq

I thought rules were supposed to just run as the owner of the table they
were defined on.  If I grant permissions on the sequence directly, then
those users could mess with its values, couldn't they?

select version();
                                version
------------------------------------------------------------------------
 PostgreSQL 7.1beta4 on i586-pc-linux-gnu, compiled by GCC egcs-2.91.66

--
Rick Delaney
rick@consumercontact.com