diff --git a/websocket-sharp/Net/HttpListenerRequest.cs b/websocket-sharp/Net/HttpListenerRequest.cs
index 8dc8651c..2d3334f6 100644
--- a/websocket-sharp/Net/HttpListenerRequest.cs
+++ b/websocket-sharp/Net/HttpListenerRequest.cs
@@ -542,7 +542,7 @@ namespace WebSocketSharp.Net
           return null;
 
         if (_userLanguages == null)
-          _userLanguages = val.Split (',');
+          _userLanguages = val.Split (',').Trim ().ToList ().ToArray ();
 
         return _userLanguages;
       }