diff --git a/src/libnpsharp/NPClient.cs b/src/libnpsharp/NPClient.cs
index 63d40d4..57e8778 100644
--- a/src/libnpsharp/NPClient.cs
+++ b/src/libnpsharp/NPClient.cs
@@ -108,7 +108,10 @@ namespace NPSharp
 
             _rpc.AttachCallback(packet =>
             {
-                var result = (AuthenticateResultMessage) packet;
+                var result = packet as AuthenticateResultMessage;
+                if (result == null)
+                    return;
+
                 if (result.Result != 0)
                     tcs.SetResult(false);
                 LoginId = result.NPID;
diff --git a/src/libnpsharp/RPC/Messages/RPCClientMessage.cs b/src/libnpsharp/RPC/Messages/RPCClientMessage.cs
index d4bd842..ab09095 100644
--- a/src/libnpsharp/RPC/Messages/RPCClientMessage.cs
+++ b/src/libnpsharp/RPC/Messages/RPCClientMessage.cs
@@ -17,7 +17,7 @@ namespace NPSharp.RPC.Messages
         public byte[] Serialize(uint id)
         {
 #if DEBUG
-            Log.DebugFormat("Packet[ID={0},Type={1},TypeName={2}] {{", id, GetTypeId(), GetType().Name);
+            Log.DebugFormat("RPCClientMessage[ID={0},Type={1},TypeName={2}] {{", id, GetTypeId(), GetType().Name);
             foreach (var prop in GetType().GetProperties())
             {
                 Log.DebugFormat("\t{0} = {1}", prop.Name, prop.GetValue(this));
diff --git a/src/libnpsharp/RPC/Messages/RPCServerMessage.cs b/src/libnpsharp/RPC/Messages/RPCServerMessage.cs
index ce1eccc..c307775 100644
--- a/src/libnpsharp/RPC/Messages/RPCServerMessage.cs
+++ b/src/libnpsharp/RPC/Messages/RPCServerMessage.cs
@@ -91,8 +91,8 @@ namespace NPSharp.RPC.Messages
             packet.MessageId = pid;
 
 #if DEBUG
-            Log.DebugFormat("ServerMessage[ID={0},Type={1},TypeName={2}] {{", pid, packet.GetTypeId(), packet.GetType().Name);
-            foreach (var prop in packet.GetType().GetProperties())
+            Log.DebugFormat("RPCServerMessage[ID={0},Type={1},TypeName={2}] {{", pid, packet.GetTypeId(), packet.GetType().Name);
+            foreach (var prop in packet.GetType().GetProperties().Where(p => !(p.DeclaringType is RPCServerMessage)))
             {
                 Log.DebugFormat("\t{0} = {1}", prop.Name, prop.GetValue(packet));
             }