Permission; select currval('seq')

I need to have members of a particular user
group insert rows into a table and then determine the
recently inserted statement's primary key that was
created from a sequence with the currval() function:

select currval('bla_bla_id_seq');

I have been unable to set these permissions.
I am using 8.1.15 and as the db superuser "postgres".
I execute the following:

test=# CREATE GROUP test_group_01;
CREATE ROLE

test=# ALTER GROUP test_group_01 ADD USER ivan;
ALTER ROLE

test=# CREATE TABLE bla (bla_id serial);
NOTICE: CREATE TABLE will create implicit sequence "bla_bla_id_seq"
for serial column "bla.bla_id"
CREATE TABLE

test=# GRANT USAGE ON SEQUENCE bla_bla_id_seq TO GROUP test_group_01;
ERROR: syntax error at or near "bla_bla_id_seq" at character 25
LINE 1: GRANT USAGE ON SEQUENCE bla_bla_id_seq TO GROUP
test_group_0...
^
test=# GRANT SELECT ON bla TO GROUP test_group_01;
GRANT
test=# GRANT INSERT ON bla TO GROUP test_group_01;
GRANT

test=# GRANT USAGE ON SEQUENCE bla_bla_id_seq TO GROUP test_group_01;
ERROR: syntax error at or near "bla_bla_id_seq" at character 25
LINE 1: GRANT USAGE ON SEQUENCE bla_bla_id_seq TO GROUP
test_group_0...

Why is the "GRANT USAGE ON SEQUENCE" statement failing?
User "ivan" can insert and update table "bla" but cannot execute
"select currval('bla_bla_id_seq');" What does the db superuser
need to execute?

Thank you for your help!