NOTIFY QUESTION - Mailing list pgsql-general

From the Docs see below it implies that the WHERE clause of the update
is ignored.(
http://www.postgresql.org/docs/8.1/static/sql-createrule.html )
If I create a Rule as

CREATE RULE foo_update_false AS ON UPDATE TO foo
   WHERE NEW.some_flag = TRUE
   DO NOTIFY foo_update;


Does the WHERE clause in the rule get ignored as well?  If so Could I
create a regular trigger and do the notification from within the trigger
having put a check in the  trigger?

Thanks,

Oisin