PostGreSQL 8.1.0 : out of memory during vacuum full analyze

Hello,

This is my first posting in this mailing list and I am a PostGreSQL newbie.
I've posted this message in the "novice" mailing list last friday, but I
have any response.
I hope somenone could help me.

I realize a benchmarck on PostGreSQL on a 300Gb database. I used the
release 8.1.0.

I have created my database, which contains 8 tables, loaded each table
and created the appropriate indexes.
Then, on each table, I have launched the "VACUUM FULL ANALYZE" command
as a non-root user.

This command failed on the last table, the biggest, called "lineitem"
which contains 1799989091 rows (near 300 Gb of datas).
This description of this table is :
TPCH=# \d lineitem
Table "public.lineitem"
Column | Type | Modifiers
-----------------+-----------------------+-----------
l_orderkey | bigint | not null
l_partkey | bigint | not null
l_suppkey | bigint | not null
l_linenumber | bigint | not null
l_quantity | numeric |
l_extendedprice | numeric |
l_discount | numeric |
l_tax | numeric | not null
l_returnflag | character(1) |
l_linestatus | character(1) |
l_shipdate | date |
l_commitdate | date |
l_receiptdate | date |
l_shipinstruct | character(25) |
l_shipmode | character(10) |
l_comment | character varying(44) |
Indexes:
"i_l_orderkey" btree (l_orderkey), tablespace "tb_index"
Tablespace: "tb_lit"

Three hours after having launched the command, I've got this error :<>

<>TPCH=# VACUUM FULL VERBOSE ANALYZE lineitem;
<>INFO: vacuuming "public.lineitem"
<>*ERROR: out of memory*
DETAIL: Failed on request of size 67108864.

I do not try to launch again a vacuum full analyze on this table.

Can someone tell me why this error appears ?
Thank you for your help.

Regards,
Alexandra DANTE