Add support of the additional SMTP driver options

src/TransportManager.php

@@ -23,6 +23,30 @@ public static function createSmtpDriver($config)
         $transport->setUsername($setting['username'] ?? $config->getEmail());
         $transport->setPassword($setting['pass']);
 
+        return self::configureSmtpDriver($transport, $provider);
+    }
+
+    /**
+     * Configure the additional SMTP driver options.
+     *
+     * @param  \Swift_SmtpTransport  $transport
+     * @param  array  $config
+     * @return \Swift_SmtpTransport
+     */
+    protected static function configureSmtpDriver($transport, $config)
+    {
+        if (isset($config['stream'])) {
+            $transport->setStreamOptions($config['stream']);
+        }
+
+        if (isset($config['source_ip'])) {
+            $transport->setSourceIp($config['source_ip']);
+        }
+
+        if (isset($config['local_domain'])) {
+            $transport->setLocalDomain($config['local_domain']);
+        }
+
         return $transport;
     }