Specifying connection charset throws exception

[Glideh]

config.yml

doctrine:
    dbal:
        default_connection:       default
        connections:
            default:
#...
            aca:
                driver_class: \Realestate\MssqlBundle\Driver\PDODblib\Driver
#...
                charset: French_CI_AS

Gives

An exception occurred while executing 'SET NAMES French_CI_AS':

SQLSTATE[HY000]: General error: 195 General SQL Server error: Check messages from the SQL Server [195](severity 15) []

Seems like it's trying a non SQL Server command