Mantis#1798. Thank you kindly, StrawberryFride for a patch that:

Fixes a couple of places where null reference exceptions were 
being caught and ignored rather than null checks being performed.

OpenSim/Region/Environment/Scenes/InnerScene.cs

@@ -95,21 +95,13 @@ namespace OpenSim.Region.Environment.Scenes
                 // If we're not doing the initial set
                 // Then we've got to remove the previous
                 // event handler
-                try
-                {
+
+                if (_PhyScene != null) 
                     _PhyScene.OnPhysicsCrash -= physicsBasedCrash;
-                }
-                catch (NullReferenceException)
-                {
-                    // This occurs when storing to _PhyScene the first time.
-                    // Is there a better way to check the event handler before
-                    // getting here
-                    // This can be safely ignored.  We're setting the first inital
-                    // there are no event handler's registered.
-                }
 
                 _PhyScene = value;
 
+                if (_PhyScene != null)
                     _PhyScene.OnPhysicsCrash += physicsBasedCrash;
             }
         }

OpenSim/Region/Environment/Scenes/SimStatsReporter.cs

@@ -153,7 +153,7 @@ namespace OpenSim.Region.Environment.Scenes
                 try
                 {
                     IEstateModule estateModule = m_scene.RequestModuleInterface<IEstateModule>();
-                    statpack.Region.RegionFlags = estateModule.GetRegionFlags();
+                    statpack.Region.RegionFlags = estateModule != null ? estateModule.GetRegionFlags() : (uint) 0;
                 }
                 catch (Exception)
                 {