The following ZendCasts cast, shows a way to use doctrine 2 in a zend framework environment.
Using this configuration, how can I make the connection use a utf-8 charset          
        
It is possible to add it via application.ini, provided you use ZendX_Doctrine2 (at https://github.com/mridgway/ZendX_Doctrine2) with MySQL.
Then here's the line you need in application.ini:
resources.entitymanagerfactory.connectionOptions.driverOptions.1002 = "SET NAMES utf8"
(1002 == PDO::MYSQL_ATTR_INIT_COMMAND)
Don't forget to correctly set
default-character-set=utf8
in your my.cnf
You could set the default table charset like that to utf8:
// Create new Doctrine Manager instance
$doctrineManager = Doctrine_Manager::getInstance();
// Set charset to UTF8
$doctrineManager->setAttribute(
    Doctrine_Core::ATTR_DEFAULT_TABLE_CHARSET,
    'utf8'
);
Quote:
an _initDoctrine method in the Bootstratp file ?
Yes.
works fine for me
resources.doctrine.dbal.connections.default.parameters.driverOptions.1002 = "SET NAMES 'UTF8'"
1002 is the integer value of PDO::MYSQL_ATTR_INIT_COMMAND:
Command to execute when connecting to the MySQL server. Will automatically be re-executed when reconnecting. Note, this constant can only be used in the driver_options array when constructing a new database handle.
For LoSo library and Doctrine 2 and MySQL add
resources.doctrine2.connection.driverOptions.1002 = "SET NAMES 'UTF8'"
to your application.ini
this worked for me. config/autoload/doctrine.local.php
<?php
return array(
    'doctrine' => array(
        'connection' => array(
            'orm_default' => array(
                'driverClass' => 'Doctrine\DBAL\Driver\PDOMySql\Driver',
                'params' => array(
                    'host' => 'localhost',
                    'port' => '3306',
                    'user' => '...',
                    'password' => '...',
                    'dbname' => '...',
                    'driverOptions' => array(
                        \PDO::MYSQL_ATTR_INIT_COMMAND => 'SET NAMES utf8'
                    )
                ),
            )
        )
    )
);
                                                                        Since this is for Doctrine 2, and ZendCasts is using Bisna, I believe you can just add this to your configuration.ini file
resources.doctrine.dbal.connections.default.parameters.driverOptions.charset = "utf8"
I'm not exactly sure how to test if it is sticking or not but let us know.