diff --git a/OpenSim/Region/ClientStack/Linden/UDP/LLUDPServer.cs b/OpenSim/Region/ClientStack/Linden/UDP/LLUDPServer.cs
index a130ffe564..9504f15b28 100644
--- a/OpenSim/Region/ClientStack/Linden/UDP/LLUDPServer.cs
+++ b/OpenSim/Region/ClientStack/Linden/UDP/LLUDPServer.cs
@@ -1692,6 +1692,9 @@ namespace OpenSim.Region.ClientStack.LindenUDP
                 endPoint = (IPEndPoint)array[0];
                 CompleteAgentMovementPacket packet = (CompleteAgentMovementPacket)array[1];
 
+                m_log.DebugFormat(
+                    "[LLUDPSERVER]: Handling CompleteAgentMovement request from {0} in {1}", endPoint, m_scene.Name);
+
                 // Determine which agent this packet came from
                 // We need to wait here because in when using the OpenSimulator V2 teleport protocol to travel to a destination
                 // simulator with no existing child presence, the viewer (at least LL 3.3.4) will send UseCircuitCode 
@@ -1703,24 +1706,36 @@ namespace OpenSim.Region.ClientStack.LindenUDP
                 {
                     if (m_scene.TryGetClient(endPoint, out client))
                     {
-                        if (client.IsActive)
-                        {
-                            break;
-                        }
-                        else
+                        if (!client.IsActive)
                         {
                             // This check exists to catch a condition where the client has been closed by another thread
                             // but has not yet been removed from the client manager (and possibly a new connection has
                             // not yet been established).
                             m_log.DebugFormat(
-                                "[LLUDPSERVER]: Received a CompleteMovementIntoRegion from {0} for {1} in {2} but client is not active.  Waiting.",
+                                "[LLUDPSERVER]: Received a CompleteAgentMovement from {0} for {1} in {2} but client is not active yet.  Waiting.",
                                 endPoint, client.Name, m_scene.Name);
                         }
+                        else if (client.SceneAgent == null)
+                        {
+                            // This check exists to catch a condition where the new client has been added to the client
+                            // manager but the SceneAgent has not yet been set in Scene.AddNewClient().  If we are too
+                            // eager, then the new ScenePresence may not have registered a listener for this messsage
+                            // before we try to process it.
+                            // XXX: A better long term fix may be to add the SceneAgent before the client is added to 
+                            // the client manager
+                            m_log.DebugFormat(
+                                "[LLUDPSERVER]: Received a CompleteAgentMovement from {0} for {1} in {2} but client SceneAgent not set yet.  Waiting.",
+                                endPoint, client.Name, m_scene.Name);
+                        }
+                        else
+                        {
+                            break;
+                        }
                     }
                     else
                     {
                         m_log.DebugFormat(
-                            "[LLUDPSERVER]: Received a CompleteMovementIntoRegion from {0} in {1} but no client exists.  Waiting.", 
+                            "[LLUDPSERVER]: Received a CompleteAgentMovement from {0} in {1} but no client exists yet.  Waiting.", 
                             endPoint, m_scene.Name);
                     }
 
@@ -1730,19 +1745,19 @@ namespace OpenSim.Region.ClientStack.LindenUDP
                 if (client == null)
                 {
                     m_log.DebugFormat(
-                        "[LLUDPSERVER]: No client found for CompleteMovementIntoRegion from {0} in {1} after wait.  Dropping.",
+                        "[LLUDPSERVER]: No client found for CompleteAgentMovement from {0} in {1} after wait.  Dropping.",
                         endPoint, m_scene.Name);
 
                     return;
                 }
-                else if (!client.IsActive)
+                else if (!client.IsActive || client.SceneAgent == null)
                 {
                     // This check exists to catch a condition where the client has been closed by another thread
                     // but has not yet been removed from the client manager.
                     // The packet could be simply ignored but it is useful to know if this condition occurred for other debugging
                     // purposes.
                     m_log.DebugFormat(
-                        "[LLUDPSERVER]: Received a CompleteMovementIntoRegion from {0} for {1} in {2} but client is not active after wait.  Dropping.",
+                        "[LLUDPSERVER]: Received a CompleteAgentMovement from {0} for {1} in {2} but client is not active after wait.  Dropping.",
                         endPoint, client.Name, m_scene.Name);
 
                     return;
@@ -1767,7 +1782,7 @@ namespace OpenSim.Region.ClientStack.LindenUDP
             catch (Exception e)
             {
                 m_log.ErrorFormat(
-                    "[LLUDPSERVER]: CompleteMovementIntoRegion handling from endpoint {0}, client {1} {2} failed.  Exception {3}{4}",
+                    "[LLUDPSERVER]: CompleteAgentMovement handling from endpoint {0}, client {1} {2} failed.  Exception {3}{4}",
                     endPoint != null ? endPoint.ToString() : "n/a",
                     client != null ? client.Name : "unknown",
                     client != null ? client.AgentId.ToString() : "unknown",
diff --git a/OpenSim/Region/Framework/Scenes/Scene.cs b/OpenSim/Region/Framework/Scenes/Scene.cs
index bc5a67fc9b..3dc509b728 100644
--- a/OpenSim/Region/Framework/Scenes/Scene.cs
+++ b/OpenSim/Region/Framework/Scenes/Scene.cs
@@ -2863,6 +2863,9 @@ namespace OpenSim.Region.Framework.Scenes
     
                 // We must set this here so that TriggerOnNewClient and TriggerOnClientLogin can determine whether the
                 // client is for a root or child agent.
+                // XXX: This may be better set for a new client before that client is added to the client manager.
+                // But need to know what happens in the case where a ScenePresence is already present (and if this 
+                // actually occurs).
                 client.SceneAgent = sp;
 
                 // This is currently also being done earlier in NewUserConnection for real users to see if this