I have exactly the same problem. My error pages don't render "Symfony\Bundle\TwigBundle\Controller\ExceptionController" anymore instead It likes in symfony 2.2.0 error pages are rendered with "Symfony\Component\HttpKernel\Debug\ExceptionHandler" in dev environment. In prod error pages are not rendered at all. I can't get symfony 2.2.0 to render my custom error pages in prod environment.

I found solution.
If you want to replace default twig error controller with your own first you must create your own controller that extend "Symfony\Bundle\TwigBundle\Controller\ExceptionController" and override "showAction(Request $request, FlattenException $exception, DebugLoggerInterface $logger = null, $format = 'html')" method or create controller like "Symfony\Bundle\TwigBundle\Controller\ExceptionController".
Second you must register this controller as service like this for example

<parameters>
    <parameter key="my_twig.controller.exception.class">Bundle\MyTwigBundle\Controller\ExceptionController</parameter>
</parameters>

<services>
    <service id="my_twig.controller.exception" class="%my_twig.controller.exception.class%">
        <argument type="service" id="twig" />
        <argument>%kernel.debug%</argument>
    </service>
</services>

Third in your configuration file (config.yml) add this

twig:
    exception_controller: my_twig.controller.exception:showAction

not like documentation says

twig:
    exception_controller: <full_namespace\controller_name>::showAction

This should be added in documentation for symfony 2.2.0

So this can be considered as a not yet documented BC break? The change is only mentioned in TwigBundle's CHANGELOG file in 35d63df.

The service definition can be stripped down a bit to something like

<service id="my_twig.controller.exception"
        class="%my_twig.controller.exception.class%"
        parent="twig.controller.exception">
</service>

@craue I agree with your service definition.

That bug aside, would #7446 also meet your needs?

The reference needs to be updated: http://symfony.com/doc/2.2/reference/configuration/twig.html#config-twig-exception-controller

In SO there is an answer to this problem as well: http://stackoverflow.com/a/15773923/267705

Closing this old ticket.