Case Insensitive Foreign Key Constraint

Hi all,

Is there a way to have text-type foreign keys be case insensitive?

development=# CREATE TABLE foo (foo text PRIMARY KEY);

NOTICE: CREATE TABLE / PRIMARY KEY will create implicit index "foo_pkey" for table "foo"
CREATE TABLE

development=# INSERT INTO foo VALUES ('foo');
INSERT 0 1

development=# CREATE TABLE foo1 (foo text REFERENCES foo);
CREATE TABLE

development=# INSERT INTO foo1 VALUES ('FOO');

ERROR: insert or update on table "foo1" violates foreign key constraint "foo1_foo_fkey"
DETAIL: Key (foo)=(FOO) is not present in table "foo".

Thanks,
George