BUG #7970: How 's list all members in a special tablespace ( not as pg_global & pg_default )

The following bug has been logged on the website:

Bug reference: 7970
Logged by: How 's list all members in a special tablespace
Email address: sunny99991982(at)yahoo(dot)com(dot)vn
PostgreSQL version: 9.0.4
Operating system: Enterpride linux 5 x86_64
Description:

I tried this, which will get the list of tables belong to 'XYZ' tablespace.

CREATE TABLESPACE TBS1 OWNER access LOCATION '/u03/tbs';

--> OK

Create table public.SinhVien ( MaSV text, TenSV text, Sodt int ) tablespace
TBS1;

--> OK

Insert into public.SinhVien (MaSV,TenSV,Sodt) Values ('001','Nguyen
Van',123456789),('002','Nguyen Ha',987654321);

--> OK

select relname from pg_class where reltablespace=(select oid from
pg_tablespace where spcname='TBS1');

relname
---------
(0 rows)

why's return 0 rows ? i don't know

please help me.