Description:
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When using PDO pgSQL with persistent connections and restarting the PostgreSQL server, which the PDO has been connected with, PDO raises exception (see below). So I need to restart PHP to reset persistent connections.

The bug was reproduced in two different environments:
Apache2 (multi-threaded) + mod_php + WinXP
lighttpd + PHP(FastCGI) + FreeBSD

MySQL persistent connections in the same situation works fine...

Reproduce code:
---------------
<?php
$db = new PDO( 'pgsql:host=localhost port=5432 dbname=test user=user password=secret', 'user', 'secret', array( PDO::ATTR_PERSISTENT => true ) );
echo 'ok';
?>

# /usr/local/etc/rc.d/postgresql restart

and again the above php script

Expected result:
----------------
ok

Actual result:
--------------
Unknown exception: SQLSTATE[57P01]: Admin shutdown: 7 FATAL: <closing connection on admin command> (this is my translation from russian message) server closed the connection unexpectedly This probably means the server terminated abnormally before or while processing the request.