diff --git a/OpenSim/Framework/IScene.cs b/OpenSim/Framework/IScene.cs
index f1b4732bf0..76b731f0f3 100644
--- a/OpenSim/Framework/IScene.cs
+++ b/OpenSim/Framework/IScene.cs
@@ -102,12 +102,28 @@ namespace OpenSim.Framework
 
         bool TryGetScenePresence(UUID agentID, out object scenePresence);
 
-        T RequestModuleInterface<T>();
-        T[] RequestModuleInterfaces<T>();
-
+        /// <summary>
+        /// Register an interface to a region module.  This allows module methods to be called directly as
+        /// well as via events.  If there is already a module registered for this interface, it is not replaced
+        /// (is this the best behaviour?)
+        /// </summary>
+        /// <param name="mod"></param>
         void RegisterModuleInterface<M>(M mod);
+        
         void StackModuleInterface<M>(M mod);
 
+        /// <summary>
+        /// For the given interface, retrieve the region module which implements it.
+        /// </summary>
+        /// <returns>null if there is no registered module implementing that interface</returns>
+        T RequestModuleInterface<T>();
+
+        /// <summary>
+        /// For the given interface, retrieve an array of region modules that implement it.
+        /// </summary>
+        /// <returns>an empty array if there are no registered modules implementing that interface</returns>
+        T[] RequestModuleInterfaces<T>();
+
 //        void AddCommand(object module, string command, string shorthelp, string longhelp, CommandDelegate callback);
 
         ISceneObject DeserializeObject(string representation);
diff --git a/OpenSim/Region/Framework/Scenes/Scene.Inventory.cs b/OpenSim/Region/Framework/Scenes/Scene.Inventory.cs
index 663aa22efb..26eb7290ac 100644
--- a/OpenSim/Region/Framework/Scenes/Scene.Inventory.cs
+++ b/OpenSim/Region/Framework/Scenes/Scene.Inventory.cs
@@ -82,16 +82,9 @@ namespace OpenSim.Region.Framework.Scenes
             m_log.Info("[PRIM INVENTORY]: Starting scripts in scene");
 
             IScriptModule[] engines = RequestModuleInterfaces<IScriptModule>();
-            if (engines != null)
-            {
-                foreach (IScriptModule engine in engines)
-                {
-                    if (engine != null)
-                    {
-                        engine.StartProcessing();
-                    }
-                }
-            }
+
+            foreach (IScriptModule engine in engines)
+                engine.StartProcessing();
         }
 
         public void AddUploadedInventoryItem(UUID agentID, InventoryItemBase item)
diff --git a/OpenSim/Region/Framework/Scenes/SceneBase.cs b/OpenSim/Region/Framework/Scenes/SceneBase.cs
index dee2ecb291..0336fe5a42 100644
--- a/OpenSim/Region/Framework/Scenes/SceneBase.cs
+++ b/OpenSim/Region/Framework/Scenes/SceneBase.cs
@@ -449,7 +449,7 @@ namespace OpenSim.Region.Framework.Scenes
             }
             else
             {
-                return new T[] { default(T) };
+                return new T[] {};
             }
         }
         
diff --git a/OpenSim/Region/Framework/Scenes/SceneObjectPartInventory.cs b/OpenSim/Region/Framework/Scenes/SceneObjectPartInventory.cs
index 94467414eb..d80944b554 100644
--- a/OpenSim/Region/Framework/Scenes/SceneObjectPartInventory.cs
+++ b/OpenSim/Region/Framework/Scenes/SceneObjectPartInventory.cs
@@ -232,8 +232,6 @@ namespace OpenSim.Region.Framework.Scenes
             ArrayList ret = new ArrayList();
 
             IScriptModule[] engines = m_part.ParentGroup.Scene.RequestModuleInterfaces<IScriptModule>();
-            if (engines == null) // No engine at all
-                return ret;
 
             foreach (IScriptModule e in engines)
             {
@@ -329,7 +327,7 @@ namespace OpenSim.Region.Framework.Scenes
         private void RestoreSavedScriptState(UUID oldID, UUID newID)
         {
             IScriptModule[] engines = m_part.ParentGroup.Scene.RequestModuleInterfaces<IScriptModule>();
-            if (engines == null) // No engine at all
+            if (engines.Length == 0) // No engine at all
                 return;
 
             if (m_part.ParentGroup.m_savedScriptState.ContainsKey(oldID))
@@ -369,6 +367,7 @@ namespace OpenSim.Region.Framework.Scenes
 
                     m_part.ParentGroup.m_savedScriptState[oldID] = newDoc.OuterXml;
                 }
+                
                 foreach (IScriptModule e in engines)
                 {
                     if (e != null)
@@ -377,6 +376,7 @@ namespace OpenSim.Region.Framework.Scenes
                             break;
                     }
                 }
+
                 m_part.ParentGroup.m_savedScriptState.Remove(oldID);
             }
         }
@@ -1129,7 +1129,7 @@ namespace OpenSim.Region.Framework.Scenes
             
             IScriptModule[] engines = m_part.ParentGroup.Scene.RequestModuleInterfaces<IScriptModule>();
             
-            if (engines == null) // No engine at all
+            if (engines.Length == 0) // No engine at all
                 return ret;
 
             List<TaskInventoryItem> scripts = GetInventoryScripts();
@@ -1157,7 +1157,7 @@ namespace OpenSim.Region.Framework.Scenes
         public void ResumeScripts()
         {
             IScriptModule[] engines = m_part.ParentGroup.Scene.RequestModuleInterfaces<IScriptModule>();
-            if (engines == null)
+            if (engines.Length == 0)
                 return;
 
             List<TaskInventoryItem> scripts = GetInventoryScripts();
diff --git a/OpenSim/Region/Framework/Scenes/ScenePresence.cs b/OpenSim/Region/Framework/Scenes/ScenePresence.cs
index 7d901c9b10..c2d3501825 100644
--- a/OpenSim/Region/Framework/Scenes/ScenePresence.cs
+++ b/OpenSim/Region/Framework/Scenes/ScenePresence.cs
@@ -3525,23 +3525,23 @@ namespace OpenSim.Region.Framework.Scenes
         /// <param name="args">The arguments for the event</param>
         public void SendScriptEventToAttachments(string eventName, Object[] args)
         {
-            if (m_scriptEngines != null)
-            {
-                lock (m_attachments)
-                {
-                    foreach (SceneObjectGroup grp in m_attachments)
-                    {
-                        // 16384 is CHANGED_ANIMATION
-                        //
-                        // Send this to all attachment root prims
-                        //
-                        foreach (IScriptModule m in m_scriptEngines)
-                        {
-                            if (m == null) // No script engine loaded
-                                continue;
+            if (m_scriptEngines.Length == 0)
+                return;
 
-                            m.PostObjectEvent(grp.RootPart.UUID, "changed", new Object[] { (int)Changed.ANIMATION });
-                        }
+            lock (m_attachments)
+            {
+                foreach (SceneObjectGroup grp in m_attachments)
+                {
+                    // 16384 is CHANGED_ANIMATION
+                    //
+                    // Send this to all attachment root prims
+                    //
+                    foreach (IScriptModule m in m_scriptEngines)
+                    {
+                        if (m == null) // No script engine loaded
+                            continue;
+
+                        m.PostObjectEvent(grp.RootPart.UUID, "changed", new Object[] { (int)Changed.ANIMATION });
                     }
                 }
             }