Sorry, thoughtI had added that :/

Missing file from pervious commit

OpenSim/Framework/ProxyCodec.cs

@@ -0,0 +1,77 @@
+/*
+ * Copyright (c) Contributors, http://opensimulator.org/
+ * See CONTRIBUTORS.TXT for a full list of copyright holders.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *     * Redistributions of source code must retain the above copyright
+ *       notice, this list of conditions and the following disclaimer.
+ *     * Redistributions in binary form must reproduce the above copyright
+ *       notice, this list of conditions and the following disclaimer in the
+ *       documentation and/or other materials provided with the distribution.
+ *     * Neither the name of the OpenSim Project nor the
+ *       names of its contributors may be used to endorse or promote products
+ *       derived from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE DEVELOPERS ``AS IS'' AND ANY
+ * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+ * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED. IN NO EVENT SHALL THE CONTRIBUTORS BE LIABLE FOR ANY
+ * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+ * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+ * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+using System;
+using System.Collections;
+using System.Net;
+using libsecondlife;
+using libsecondlife.Packets;
+
+namespace OpenSim.Framework
+{
+    public sealed class ProxyCodec
+    {
+        public static void EncodeProxyMessage(byte[] bytes, ref int numBytes, EndPoint trueEP)
+        {
+            if (numBytes > 4090) // max UPD size = 4096
+            {
+                throw new Exception("ERROR: No space to encode the proxy EP");
+            }
+
+            ushort port = (ushort) ((IPEndPoint) trueEP).Port;
+            bytes[numBytes++] = (byte) (port % 256);
+            bytes[numBytes++] = (byte) (port / 256);
+
+            foreach (byte b in ((IPEndPoint) trueEP).Address.GetAddressBytes())
+            {
+                bytes[numBytes++] = b;
+            }
+
+            int x = numBytes;
+
+            DecodeProxyMessage(bytes, ref numBytes);
+
+            numBytes = x;
+        }
+
+        public static EndPoint DecodeProxyMessage(byte[] bytes, ref int numBytes)
+        {
+            // IPv4 Only
+            byte[] addr = new byte[4];
+
+            addr[3] = bytes[--numBytes];
+            addr[2] = bytes[--numBytes];
+            addr[1] = bytes[--numBytes];
+            addr[0] = bytes[--numBytes];
+
+            ushort port = (ushort) (bytes[--numBytes] * 256);
+            port += (ushort) bytes[--numBytes];
+
+            return (EndPoint) new IPEndPoint(new IPAddress(addr), (int) port);
+        }
+    }
+}