Can arrays reference primary keys in CREATE TABLE?

Hi,

I'm a rather new SQL user, and I found interesting that you can
use "references" to make sure that a value inserted in a table is a
primary key from another table. Something like:

create table ta (
a_id integer primary key
);
create table tb (
a_ref integer references ta(a_id)
);

However, I'd like to define a table containing an array, and that
all elements of the array be a primary key from another table, so I
tried:

create table tb (
a_ref integer[] references ta(a_id)
);

But that doesn't work, I think because an array of integers can't
be directly compared to an integer.

Is there a way to do this? (I'm using Red Hat 9 with PostgreSQL 7.3.2,
by the way.)

Thanks in advance for any answer or for pointing our where I can find
it.

Fil