Partially corrupted table

Platform:
CentOS release 4.3 (Final) (Linux 2.6.9-34.EL)

Database version:
PostgreSQL 8.1.3 on i686-redhat-linux-gnu, compiled by GCC gcc (GCC) 3.4.5 20051201 (Red Hat 3.4.5-2)

Description:
One of cca 100 tables is partially corrupted. An attempt to read or dump the data from the table is sometimes successful, sometimes crashes.
After upgrade to 8.1.4 the behaviour remained unchanged (using the cluster created with 8.1.3). Unfortunately, I am not able to reproduce the error from the beginning using ONLY 8.1.4.

Note:
After successful dump/reload everything is OK. The problem is not in the data content itself, but in the binary database cluster. This is why I would like to send you the whole cluster instead of the database dump as an attachment. The problem is in the file size (30M). Please tell me where or how to send it. For simplicity, I removed all other objects from the database. There is only one table with several indexes, the table contains 56621 rows.

Here are some examples of the bevaviour:

[root(at)devlin2 tmp]# pg_dumpall -p5447 -U postgres > pgdump.sql
pg_dump: ERROR: invalid memory alloc request size 4294967290
pg_dump: SQL command to dump the contents of table "fct" failed: PQendcopy() failed.
pg_dump: Error message from server: ERROR: invalid memory alloc request size 4294967290
pg_dump: The command was: COPY dwhdata_salemc.fct (time_id, company_id, customer_id, product_id, flagsprod_id, flagssale_id, account_id, accttime_id, invcustomer_id, salesperson_id, vendor_id, inv_cost_amt, inv_base_amt, inv_amt, inv_qty, inv_wght, ret_cost_amt, ret_base_amt, ret_amt, ret_qty, ret_wght, unret_cost_amt, unret_base_amt, unret_amt, unret_qty, unret_wght, bonus_forecast, bonus_final, stamp_code) TO stdout;
pg_dumpall: pg_dump failed on database "dwhdb", exiting

dwhdb=# create temp table t_fct as select * from dwhdata_salemc.fct;
SELECT

dwhdb=# create temp table t_fct as select * from dwhdata_salemc.fct;
server closed the connection unexpectedly
This probably means the server terminated abnormally
before or while processing the request.
The connection to the server was lost. Attempting reset: Failed.
!>

dwhdb=# create temp table t_fct as select * from dwhdata_salemc.fct;
ERROR: row is too big: size 119264, maximum size 8136

dwhdb=# create temp table t_fct as select * from dwhdata_salemc.fct;
ERROR: row is too big: size 38788, maximum size 8136

AFTER UPGRADE TO 8.1.4:
dwhdb=# create temp table t_fct as select * from dwhdata_salemc.fct;
ERROR: row is too big: size 52892, maximum size 8136

I noticed one more problem when executing vacuum:
dwhdb=# vacuum full;
WARNING: relation "pg_attribute" page 113 is uninitialized --- fixing
VACUUM

The "vacuum" problem has happend only once.

Regards
Fililp Hrbek