diff --git a/src/Ratchet/Server/IoServer.php b/src/Ratchet/Server/IoServer.php
index 1669b78..1a992fd 100644
--- a/src/Ratchet/Server/IoServer.php
+++ b/src/Ratchet/Server/IoServer.php
@@ -52,6 +52,7 @@ class IoServer {
      * @param  \Ratchet\MessageComponentInterface $component The application that I/O will call when events are received
      * @param  int                                $port      The port to server sockets on
      * @param  string                             $address   The address to receive sockets on (0.0.0.0 means receive connections from any)
+     * @param  array                              $sslconf   An array of PHP stream context options in order to support SSL
      * @return IoServer
      */
     public static function factory(MessageComponentInterface $component, $port = 80, $address = '0.0.0.0', $sslconf = null) {