You need to add the bundle to your app/AppKernel.php. This bundle also requires the MMCmfNodeBundle, so make sure this bundle is also registered.
...
public function registerBundles()
{
$bundles = array(
...
new MandarinMedien\MMCmfPageBundle\MMCmfNodeBundle(),
new MandarinMedien\MMCmfPageBundle\MMCmfRoutingBundle(),
...
);
....
}
...