diff --git a/websocket-sharp/Net/EndPointListener.cs b/websocket-sharp/Net/EndPointListener.cs
index 50458972..770f131e 100644
--- a/websocket-sharp/Net/EndPointListener.cs
+++ b/websocket-sharp/Net/EndPointListener.cs
@@ -461,58 +461,6 @@ namespace WebSocketSharp.Net
       );
     }
 
-    public void AddPrefix (HttpListenerPrefix prefix, HttpListener listener)
-    {
-      List<HttpListenerPrefix> current, future;
-      if (prefix.Host == "*") {
-        do {
-          current = _unhandled;
-          future = current != null
-                   ? new List<HttpListenerPrefix> (current)
-                   : new List<HttpListenerPrefix> ();
-
-          prefix.Listener = listener;
-          addSpecial (future, prefix);
-        }
-        while (Interlocked.CompareExchange (ref _unhandled, future, current) != current);
-
-        return;
-      }
-
-      if (prefix.Host == "+") {
-        do {
-          current = _all;
-          future = current != null
-                   ? new List<HttpListenerPrefix> (current)
-                   : new List<HttpListenerPrefix> ();
-
-          prefix.Listener = listener;
-          addSpecial (future, prefix);
-        }
-        while (Interlocked.CompareExchange (ref _all, future, current) != current);
-
-        return;
-      }
-
-      Dictionary<HttpListenerPrefix, HttpListener> prefs, prefs2;
-      do {
-        prefs = _prefixes;
-        if (prefs.ContainsKey (prefix)) {
-          if (prefs[prefix] != listener) {
-            throw new HttpListenerException (
-              87, String.Format ("There's another listener for {0}.", prefix)
-            );
-          }
-
-          return;
-        }
-
-        prefs2 = new Dictionary<HttpListenerPrefix, HttpListener> (prefs);
-        prefs2[prefix] = listener;
-      }
-      while (Interlocked.CompareExchange (ref _prefixes, prefs2, prefs) != prefs);
-    }
-
     public void Close ()
     {
       _socket.Close ();