"expected authentication request from server, but received..."

[Michał Jęczalik <pgsql-hackers(at)jeczalik(dot)com>]

	Hello,

I have a very old postgres 6.4 installation. I'm trying to connect to it 
from a fresh, up-to-date Debian-host, but I'm constantly getting (from DBI 
and PHP as well) this error message:

# ./update_dns.pl
DBI connect('dbname=dns;host=sql;authtype=password','dns',...) failed: 
expected authentication request from server, but received U
 at ./update_dns.pl line 237


Connection with psql works OK. Connecting from different (older) hosts 
with DBI/PHP works perfect as well. Something must have changed in recent 
versions of libpq and now it doesn't work. I looked into source code and 
found that the server's message at the very start of conversation appears 
to be something else than the libpq expects. But how to fix it?! Has the 
protocol change or what?

P.S. Don't tell me to upgrade postgres :) It must stay like that for some 
reasons which are beyond me.
--
Samotnik Michał Jęczalik, +48.695.64.75.14
www.zagle.org.pl   - rejsy morskie