Failed sending email with cakephp 3.1 | stream_socket_client()

Question

I have a problem with CakePHP 3.1 on my virtual server.

When I try to send e-mails on localhost, everything works perfect, no errors, no warnings.

However when I try to send e-mails on vserver, I receive the following error:

2016-01-06 11:07:33 Error: [Cake\Network\Exception\SocketException] stream_socket_client() [<a href='http://php.net/function.stream-socket-clien
t'>function.stream-socket-client</a>]: Peer certificate CN=`smtp.gmail.com' did not match expected CN=`ssl://smtp.gmail.com'
stream_socket_client() [<a href='http://php.net/function.stream-socket-client'>function.stream-socket-client</a>]: Failed to enable crypto
stream_socket_client() [<a href='http://php.net/function.stream-socket-client'>function.stream-socket-client</a>]: unable to connect to ssl://sm
tp.gmail.com:465 (Unknown error)

I have already tried to change the email configuration in app.php by adding the following:

'ssl' => [
        'verify_peer'  => false,
        'verify_peer_name'  => false,
        'allow_self_signed' => true
],

This did not fix the problem.

Does anyone got a hint or solution for that problem?