./configure' '--with-apache=../apache_1.3.14' '--enable-track-vars' '--enable-ftp' '--enable-trans-sid' '--disable-debug' '--enable-magic-quotes'

<?
$conn=mysql_ponnect("localhost","user","pass");

$r=mysql_db_query("mydb","update x='y' where z='p' ",$conn);

$n=mysql_affected_rows($r);

echo "n= $n";
?>
It prints "n= " and I get this warning:
Warning: Supplied argument is not a valid MySQL-Link resource in /mnt/clientes/sancho/html/classes/manage_users.php on line 143

but the data in the database is beeing modified by the update query. It worked fine with 4.0.1pl2

php.ini:

[MySQL]
mysql.allow_persistent	=	On	
mysql.max_persistent	=	-1	
mysql.max_links			=	-1	
mysql.default_port		=		
mysql.default_host		=		
mysql.default_user		=		
mysql.default_password	=