Get rid of the spurious [WEB UTIL] couldn't decode <OpenSim agent 57956c4b-ff2e-4fc1-9995-613c6256cc98>: Invalid character 'O' in input string messages

These are just the result of an attempt to canonicalize received messages - it's not important that we constantly log them.
Also finally get the deregister grid service message working properly

OpenSim/Region/Framework/Scenes/SceneCommunicationService.cs

@@ -174,7 +174,6 @@ namespace OpenSim.Region.Framework.Scenes
             {
                 // We're ignoring a collection was modified error because this data gets old and outdated fast.
             }
-
         }
 
         /// <summary>
@@ -182,13 +181,18 @@ namespace OpenSim.Region.Framework.Scenes
         /// </summary>
         protected void SendCloseChildAgent(UUID agentID, ulong regionHandle)
         {
-            m_log.Debug("[INTERGRID]: Sending close agent to " + regionHandle);
             // let's do our best, but there's not much we can do if the neighbour doesn't accept.
 
             //m_commsProvider.InterRegion.TellRegionToCloseChildConnection(regionHandle, agentID);
             uint x = 0, y = 0;
             Utils.LongToUInts(regionHandle, out x, out y);
+
             GridRegion destination = m_scene.GridService.GetRegionByPosition(m_regionInfo.ScopeID, (int)x, (int)y);
+
+            m_log.DebugFormat(
+                "[INTERGRID]: Sending close agent {0} to region at {1}-{2}",
+                agentID, destination.RegionCoordX, destination.RegionCoordY);
+
             m_scene.SimulationService.CloseAgent(destination, agentID);
         }