select * from pgadmin_users; causes error

Hi

I'm new to postgresql.

When logged in as postgres (using psql)the following query returns an error
gsmain_test=# select * from pgadmin_users;
ERROR:  pg_shadow: Permission denied.

I can select from pg_user and pg_shadow.

The reason I am trying to run the above query is I had the same error when trying to view users/groups   from pgAdmin.

The database was created using user postgres

My system
     Linux Box
    Postgresql 7.0.3-2 installed from rpms
    Redhat 7.0

     Win98 Box
    pgAdmin v7.0.5
    odbc driver 6.50.00.00
    mdac 2.6

Thanks in advance

John