diff --git a/OpenSim/Region/ClientStack/LindenUDP/UnackedPacketCollection.cs b/OpenSim/Region/ClientStack/LindenUDP/UnackedPacketCollection.cs
index 9d40688ac6..d762bef134 100644
--- a/OpenSim/Region/ClientStack/LindenUDP/UnackedPacketCollection.cs
+++ b/OpenSim/Region/ClientStack/LindenUDP/UnackedPacketCollection.cs
@@ -141,31 +141,46 @@ namespace OpenSim.Region.ClientStack.LindenUDP
         private void ProcessQueues()
         {
             // Process all the pending adds
+
             OutgoingPacket pendingAdd;
-            while (m_pendingAdds.TryDequeue(out pendingAdd))
-                m_packets[pendingAdd.SequenceNumber] = pendingAdd;
+            if (m_pendingAdds != null)
+            {
+                while (m_pendingAdds.TryDequeue(out pendingAdd))
+                {
+                    if (pendingAdd != null && m_packets != null)
+                    {
+                        m_packets[pendingAdd.SequenceNumber] = pendingAdd;
+                    }
+                }
+            }
             
             // Process all the pending removes, including updating statistics and round-trip times
             PendingAck pendingRemove;
             OutgoingPacket ackedPacket;
-            while (m_pendingRemoves.TryDequeue(out pendingRemove))
+            if (m_pendingRemoves != null)
             {
-                if (m_packets.TryGetValue(pendingRemove.SequenceNumber, out ackedPacket))
+                while (m_pendingRemoves.TryDequeue(out pendingRemove))
                 {
-                    m_packets.Remove(pendingRemove.SequenceNumber);
-
-                    // Update stats
-                    Interlocked.Add(ref ackedPacket.Client.UnackedBytes, -ackedPacket.Buffer.DataLength);
-
-                    if (!pendingRemove.FromResend)
+                    if (m_pendingRemoves != null && m_packets != null)
                     {
-                        // Calculate the round-trip time for this packet and its ACK
-                        int rtt = pendingRemove.RemoveTime - ackedPacket.TickCount;
-                        if (rtt > 0)
-                            ackedPacket.Client.UpdateRoundTrip(rtt);
+                        if (m_packets.TryGetValue(pendingRemove.SequenceNumber, out ackedPacket))
+                        {
+                            m_packets.Remove(pendingRemove.SequenceNumber);
+
+                            // Update stats
+                            Interlocked.Add(ref ackedPacket.Client.UnackedBytes, -ackedPacket.Buffer.DataLength);
+
+                            if (!pendingRemove.FromResend)
+                            {
+                                // Calculate the round-trip time for this packet and its ACK
+                                int rtt = pendingRemove.RemoveTime - ackedPacket.TickCount;
+                                if (rtt > 0)
+                                    ackedPacket.Client.UpdateRoundTrip(rtt);
+                            }
+                        }
                     }
                 }
             }
         }
     }
-}
\ No newline at end of file
+}