diff --git a/lib/socket.io.js b/lib/socket.io.js
index ce07dca5..44a362fc 100644
--- a/lib/socket.io.js
+++ b/lib/socket.io.js
@@ -32,6 +32,9 @@ exports.clientVersion = client.version;
 /**
  * Attaches a manager
  *
+ * @param {HTTPServer/Number} a HTTP/S server or a port number to listen on.
+ * @param {Object} opts to be passed to Manager and/or http server
+ * @param {Function} callback if a port is supplied
  * @api public
  */
 
@@ -65,7 +68,7 @@ exports.listen = function (server, options, fn) {
   }
 
   // otherwise assume a http/s server
-  return new exports.Manager(server);
+  return new exports.Manager(server, options);
 };
 
 /**