symfony/src/Symfony/Bundle/FrameworkBundle/Resources/config/session.xml

<?xml version="1.0" ?>

<container xmlns="http://www.symfony-project.org/schema/dic/services"
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xsi:schemaLocation="http://www.symfony-project.org/schema/dic/services http://www.symfony-project.org/schema/dic/services/services-1.0.xsd">

    <parameters>
        <parameter key="session.class">Symfony\Component\HttpFoundation\Session</parameter>
        <parameter key="session.default_locale">en</parameter>
        <parameter key="session.storage.native.class">Symfony\Component\HttpFoundation\SessionStorage\NativeSessionStorage</parameter>
        <parameter key="session.storage.native.options" type="collection" />
        <parameter key="session.storage.pdo.class">Symfony\Component\HttpFoundation\SessionStorage\PdoSessionStorage</parameter>
        <parameter key="session.storage.pdo.options" type="collection" />
        <parameter key="session.storage.array.class">Symfony\Component\HttpFoundation\SessionStorage\ArraySessionStorage</parameter>
        <parameter key="session.storage.array.options" type="collection" />
    </parameters>

    <services>
        <service id="session" class="%session.class%">
            <argument type="service" id="session.storage" />
            <argument type="collection">
                <argument key="default_locale">%session.default_locale%</argument>
            </argument>
        </service>

        <service id="session.storage.native" class="%session.storage.native.class%" public="false">
            <argument>%session.storage.native.options%</argument>
        </service>

        <service id="session.storage.pdo" class="%session.storage.pdo.class%" public="false">
            <argument type="service" id="pdo_connection" />
            <argument>%session.storage.pdo.options%</argument>
        </service>

        <service id="session.storage.array" class="%session.storage.array.class%" public="false">
            <argument>%session.storage.array.options%</argument>
        </service>

        <service id="session.storage" alias="session.storage.native" />
    </services>
</container>