Adding columns to a view

Hi there,

is there any way to add new columns to a view without dropping and
recreating it (and thus every other view that depends on it)? A friend
of mine came up with a crude hack that involves manipulating the reltype
flag in pg_class so Postgres thinks the view is actualy a table, using
'ALTER TABLE' to add a new column, restoring the old reltype and
changing the _RETURN rule for that view to include the new column as
well. The existence of that "solution" lost me a bet and a crate of
beer, but I wouldn't really want to use it in a production-stage
database. ;-)
I could think of a few situations where extending a view might be
useful, and I'd appreciate to see it supported. I don't see any reason
not to allow it as long as no existing columns are removed or have their
type changed.

Cheers,
Ingo