- Handle NatIntroduction message even if connection already exists

Lidgren.Network/NetConnection.cs

@@ -409,6 +409,10 @@ namespace Lidgren.Network
 					int size = emsg.ReadInt32();
 					HandleExpandMTUSuccess(now, size);
 					break;
+				case NetMessageType.NatIntroduction:
+					// Unusual situation where server is actually already known, but got a nat introduction - oh well, lets handle it as usual
+					m_peer.HandleNatIntroduction(ptr);
+					break;
 				default:
 					m_peer.LogWarning("Connection received unhandled library message: " + tp);
 					break;

Lidgren.Network/NetNatIntroduction.cs

@@ -38,7 +38,7 @@ namespace Lidgren.Network
 		/// <summary>
 		/// Called when host/client receives a NatIntroduction message from a master server
 		/// </summary>
-		private void HandleNatIntroduction(int ptr)
+		internal void HandleNatIntroduction(int ptr)
 		{
 			VerifyNetworkThread();