1 files changed, 2 insertions, 2 deletions
diff --git a/Swiften/Network/NATTraversalInterface.h b/Swiften/Network/NATTraversalInterface.h
index ea9ed6a..1655eb6 100644
--- a/Swiften/Network/NATTraversalInterface.h
+++ b/Swiften/Network/NATTraversalInterface.h
@@ -1,11 +1,11 @@
 /*
- * Copyright (c) 2011-2015 Isode Limited.
+ * Copyright (c) 2011-2018 Isode Limited.
  * Licensed under the simplified BSD license.
  * See Documentation/Licenses/BSD-simplified.txt for more information.
  */
 
 #pragma once
 
 #include <boost/optional.hpp>
 
 #include <Swiften/Base/API.h>
@@ -13,13 +13,13 @@
 
 namespace Swift {
     class SWIFTEN_API NATTraversalInterface {
         public:
             virtual ~NATTraversalInterface();
 
             virtual bool isAvailable() = 0;
 
             virtual boost::optional<HostAddress> getPublicIP() = 0;
-            virtual boost::optional<NATPortMapping> addPortForward(int localPort, int publicPort) = 0;
+            virtual boost::optional<NATPortMapping> addPortForward(unsigned short localPort, unsigned short publicPort) = 0;
             virtual bool removePortForward(const NATPortMapping&) = 0;
     };
 }