BUG #4812: statistics not available on tables containing only hstore column

The following bug has been logged online:

Bug reference:      4812
Logged by:          George Su
Email address:      george.su@efrontier.com
PostgreSQL version: 8.3.6
Operating system:   SUSE Linux
Description:        statistics not available on tables containing only
hstore column
Details:

If I create a table containing only hstore columns, then no statistics on
row count and page count is available even after analyzing.

safire:9945:postgres# create table tmp_tbl (a hstore);
CREATE TABLE
safire:9945:postgres# insert into tmp_tbl select i::text => i::text from
generate_series(1, 100000) as i;
INSERT 0 100000
safire:9945:postgres# analyze tmp_tbl;
ANALYZE
safire:9945:postgres# select count(*) from tmp_tbl;
 count
--------
 100000
(1 row)

safire:9945:postgres# select relname, relpages, reltuples from pg_class
where relname = 'tmp_tbl';
 relname | relpages | reltuples
---------+----------+-----------
 tmp_tbl |        0 |         0
(1 row)

The statistics shows up if I add a, for example, int column.