Steps to reproduce the issue

If you use postgres as db backend for joomla, and there is a pgpool istance in the middle, you will have to deal with this bug:
http://www.sraoss.jp/pipermail/pgpool-general/2013-August/002124.html

Additional comments

in /libraries/joomla/database/driver/postgresql.php there is a function "connect()", that after the connection sends a query
pg_query('SET standard_conforming_strings=off');
for pgpool that will not work.
you should change the dns param

from
$dsn .= "dbname={$this->options['database']} user={$this->options['user']} password={$this->options['password']}";

to

$dsn .= "dbname={$this->options['database']} user={$this->options['user']} password={$this->options['password']} options='-c standard_conforming_strings=off'";