Explain returns extremely high cost

Hi!

I have a database just recreated from scratch with SQL script.
(My PostgreSQL version is 8.1.3).
All of the tables are pretty empty, but that's what I've got with explain:

EXPLAIN SELECT * FROM account;
                               QUERY PLAN
------------------------------------------------------------------------
 Seq Scan on account  (cost=100000000.00..100000001.05 rows=5 width=41)

This is what I have in the table:

SELECT * FROM account;
 obj_id  |  login  |  password   | client_id | service_id | type_id | state_id
---------+---------+-------------+-----------+------------+---------+----------
 1000513 | root    | _system____ |   1000471 |    1000486 | 1000113 |  1000209
 1000548 | root    | _system____ |   1000472 |    1000536 | 1000113 |  1000209
 1000550 | root    | _system____ |   1000475 |    1000534 | 1000113 |  1000209
 1000552 | sol     | _sol        |   1000472 |    1000536 | 1000113 |  1000209
 1000554 | seregik | _seregik    |   1000475 |    1000534 | 1000113 |  1000209
(5 rows)
Time: 1.346 ms

For other tables I have more or less the same high costs.

I've done VACUUM ANALYZE. This is what I have in pg_class table:

SELECT relpages,reltuples FROM pg_class WHERE relname='account';
relpages | reltuples
----------+-----------
        1 |         5

Why the costs are so high? Is it a bug?
Thanks in advance for any suggestions!
Regards, Andrii