Grant Select privileges for all tables in schema

Hi there,

I am using Postgresql 7.3 and I want to grant select rights to a user on all tables in a schema, including those that
maybe created in the future but whose names are not yet known.  I want to do something like: 

GRANT SELECT ON <schema>.* TO <user>;

but select isn't a valid privilege on a schema and I don't see how wildcards are supported.  Is there a way to do this,
ordoes a table need to exist before a user can be granted rights to it, and users must be explicitly granted rights to
eachtable and not in a 'global' way.   I would appreciate any thoughts on this. 

-Bob