nasty problem with redhat 6.2 + pg 7.02

After more than two years of using postgresql with linux, this
may turn to be my last frustration; not being able to find the
problem, and with several thousands of customers that must pay
on the FIRST day of each month, I find this NASTY; must I
turn to oracle on solaris, I wonder....

Take a look at this: if you can't spot the problem,
(I couldn't) at least you should be warned: this
seems pretty serious.

(using PGDATESTYLE=Postgres )

[postgres(at)ren postgres]$ createdb test1
CREATE DATABASE
[postgres(at)ren postgres]$ echo "create table serv2 (fecha1 date,fecha2 date);" |
psql test1
CREATE
[postgres(at)ren postgres]$ echo "insert into serv2 values
('13-01-2000','01-10-2000');"| psql test1
INSERT 380928512 1
[postgres(at)ren postgres]$ echo "select * from serv2;" | psql test1
fecha1 | fecha2
------------+------------
13-01-2000 | 30-09-2000
(1 row)


?????? What's happening here ???

The 'lost day' ( 01-10-2000 => 30-09-2000 ) occurs with
that date only, first october 2000... at least, I haven't found any
other example
The problem is rather random; (for some reason, it happens with less
'probability' :-((( if I create the table with only a field date2)

I'm using RedHat 6.2 (having suffered recently the horrible 'sort -n'
bug http://www.redhat.com/support/errata/RHBA-2000-040-01.html
I'm having less and less confidence on this platform... but...)
Actually, I could reproduce the problem in other rh 6.2 machine, but
it does not appears with another machine running RH 6.1
BUT, the problem does not reveal on another machine, which has rh 6.2
(but pg was compiled over the previous rh 6.1 distro... could that
make any difference)?

Yes, I run the (complete) regression tests. All OK.

More data follows below...

Hernan Gonzalez
Buenos Aires, Argentina
hgonzal(at)sinectis(dot)com(dot)ar

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[postgres(at)ren postgres]$ uname -a
Linux ren.sinectis.com.ar 2.2.14-5.0 #1 Tue Mar 7 21:07:39 EST 2000
i686 unknown

[postgres(at)ren postgres]$ cat /etc/redhat-release
Red Hat Linux release 6.2 (Zoot)

[postgres(at)ren postgres]$ echo "select version();" | psql test1
version
---------------------------------------------------------------------
PostgreSQL 7.0.2 on i686-pc-linux-gnu, compiled by gcc egcs-2.91.66
(1 row)

[postgres(at)ren postgres]$ set (stripped)
HOSTTYPE=i386
LANG=en_US
LOGNAME=postgres
OSTYPE=Linux

PATH=/bin:/usr/bin:/usr/local/bin:/usr/bin/X11:/usr/X11R6/bin:/home/postgres/bin:/sql/bin:
PGDATA=/sql/data
PGDATESTYLE=Postgres
PGLIB=/sql/lib
HOME=/home/postgres
HOSTTYPE=i386
UID=500
USER=postgres
USERNAME=