Force Character Set:
(If you are setting a character set in vBulletin via config.php, you should enter that value here.)
In my vbulletin config file :
// When using MySQL 4.1+, MySQLi should be used to connect to the database.
// If you need to set the default connection charset because your database
// is using a charset other than latin1, you can set the charset here.
// If you don't set the charset to be the same as your database, you
// may receive collation errors. Ignore this setting unless you
// are sure you need to use it.
// $config['Mysqli']['charset'] = 'utf8';
Should i put utf8 in the Force Character Set section ?