[Resolvido] Enviar e-mail com Zend Framework 2

Galera estou tentando criar um formulário de contato com o zend 2.

Meu código:

$mail = new Mail\Message();
 $mail->setBody('This is the text of the email.');
 $mail->setFrom('sobreira.michel@gmail.com', 'Sender\'s name');
 $mail->addTo('sobreira.michel@gmail.com', 'Name o. recipient');
 $mail->setSubject('TestSubject');

 $transport = new Mail\Transport\Sendmail();
 $transport->send($mail);

Mais da a seguinte mensagem de erro:

Parece que alguma coisa no meu PC está bloqueando o envio. Se alguém puder me ajudar! :grin:/>

Additional information:
Zend\Mail\Exception\RuntimeException
File:
/home/michel/Dropbox/portifolio/vendor/zendframework/zendframework/library/Zend/Mail/Transport/Sendmail.php:288
Message:
Unable to send mail: Unknown error
Stack trace:
#0 [internal function]: Zend\Mail\Transport\Sendmail->mailHandler('Name o. recipie...', 'TestSubject', 'This is the tex...', 'Date: Sun, 02 D...', ' -r sobreira.mi...')
#1 /home/michel/Dropbox/portifolio/vendor/zendframework/zendframework/library/Zend/Mail/Transport/Sendmail.php(136): call_user_func(Array, 'Name o. recipie...', 'TestSubject', 'This is the tex...', 'Date: Sun, 02 D...', ' -r sobreira.mi...')
#2 /home/michel/Dropbox/portifolio/module/Site/src/Site/Controller/IndexController.php(49): Zend\Mail\Transport\Sendmail->send(Object(Zend\Mail\Message))
#3 /home/michel/Dropbox/portifolio/vendor/zendframework/zendframework/library/Zend/Mvc/Controller/AbstractActionController.php(87): Site\Controller\IndexController->indexAction()
#4 [internal function]: Zend\Mvc\Controller\AbstractActionController->onDispatch(Object(Zend\Mvc\MvcEvent))
#5 /home/michel/Dropbox/portifolio/vendor/zendframework/zendframework/library/Zend/EventManager/EventManager.php(468): call_user_func(Array, Object(Zend\Mvc\MvcEvent))
#6 /home/michel/Dropbox/portifolio/vendor/zendframework/zendframework/library/Zend/EventManager/EventManager.php(208): Zend\EventManager\EventManager->triggerListeners('dispatch', Object(Zend\Mvc\MvcEvent), Object(Closure))
#7 /home/michel/Dropbox/portifolio/vendor/zendframework/zendframework/library/Zend/Mvc/Controller/AbstractController.php(108): Zend\EventManager\EventManager->trigger('dispatch', Object(Zend\Mvc\MvcEvent), Object(Closure))
#8 /home/michel/Dropbox/portifolio/vendor/zendframework/zendframework/library/Zend/Mvc/DispatchListener.php(113): Zend\Mvc\Controller\AbstractController->dispatch(Object(Zend\Http\PhpEnvironment\Request), Object(Zend\Http\PhpEnvironment\Response))
#9 [internal function]: Zend\Mvc\DispatchListener->onDispatch(Object(Zend\Mvc\MvcEvent))
#10 /home/michel/Dropbox/portifolio/vendor/zendframework/zendframework/library/Zend/EventManager/EventManager.php(468): call_user_func(Array, Object(Zend\Mvc\MvcEvent))
#11 /home/michel/Dropbox/portifolio/vendor/zendframework/zendframework/library/Zend/EventManager/EventManager.php(208): Zend\EventManager\EventManager->triggerListeners('dispatch', Object(Zend\Mvc\MvcEvent), Object(Closure))
#12 /home/michel/Dropbox/portifolio/vendor/zendframework/zendframework/library/Zend/Mvc/Application.php(296): Zend\EventManager\EventManager->trigger('dispatch', Object(Zend\Mvc\MvcEvent), Object(Closure))
#13 /home/michel/Dropbox/portifolio/public/index.php(12): Zend\Mvc\Application->run()
#14 {main}