How to force Symfony 3 to use Memcached instead of Memcache class

Question

I am running php7 on debian and I do only have the php7-memcached extension available since php-memcache appears to be deprecated or not compatible with php7.

When I run my Symfony 3.2.8 setup with composer some post-install-cmd's are executed like

Sensio\\Bundle\\DistributionBundle\\Composer\\ScriptHandler::clearCache
Sensio\\Bundle\\DistributionBundle\\Composer\\ScriptHandler::installAssets

For some reason they require the memcache extension instead of the memcached extension which is installed and loaded with the php cli. So the execution results in the follow error:

[Symfony\Component\Debug\Exception\FatalThrowableError]
Class 'Memcache' not found


Script Sensio\Bundle\DistributionBundle\Composer\ScriptHandler::installAssets handling the symfony-scripts event terminated with an exception


[RuntimeException]
An error occurred when executing the "'assets:install --symlink --relative '\''web'\'''" command:

    [Symfony\Component\Debug\Exception\FatalThrowableError]
    Class 'Memcache' not found

Is there any way to make Symfony use the Memcached class of the available extension instead of the Memcache class? I've checked some app configurations which specify Memcache as class and modified them to Memcached without success. I couldn't find a configuration which might be related to the Debug Component specified in the exception.