Error connection on vBulletin

[ghisirds]

So, I looked for in file config.php (inside include folder) the entry that can be like the error's one and I found this:

// ****** MASTER DATABASE SERVER NAME AND PORT ******
// This is the hostname or IP address and port of the database server.
// If you are unsure of what to put here, leave the default values.
$config['MasterServer']['servername'] = '213.215.228.XXX;
$config['MasterServer']['port'] = 3306;

Really the xxx of the number 213.215.228.XXX hide digits but are not the same as the ones reported in the error.
I have tried to substitute the file in this way and to upload again on the server:

// ****** MASTER DATABASE SERVER NAME AND PORT ******
// This is the hostname or IP address and port of the database server.
// If you are unsure of what to put here, leave the default values.
$config['MasterServer']['servername'] = 'localhost';
$config['MasterServer']['port'] = 3306;

But the problem is that the error stay, even if different...!!

Database error in vBulletin :

mysql_connect(): Access denied for user 'pippo'@'localhost' (using password: YES)
/var/www/vhosts/dominio.estensione/httpdocs/includes/class_core.php on line 274

MySQL Error :
Error Number :
Date : Friday, August 1st 2008 @ 04:46:23 PM
Script : http ://dominio.estensione/tags/romano/
Referrer :
IP Address : 72.36.115.XXX
Username :
Classname : vb_database

How can I solve it?
Thak you very much