diff --git a/websocket-sharp/Net/HttpListenerResponse.cs b/websocket-sharp/Net/HttpListenerResponse.cs
index 5bcd3dd6..a395a879 100644
--- a/websocket-sharp/Net/HttpListenerResponse.cs
+++ b/websocket-sharp/Net/HttpListenerResponse.cs
@@ -616,7 +616,7 @@ namespace WebSocketSharp.Net
         yield break;
 
       foreach (var c in _cookies) {
-        if (c.EqualsWithoutValue (cookie))
+        if (c.EqualsWithoutValueAndVersion (cookie))
           yield return c;
       }
     }