diff --git a/OpenSim/Region/OptionalModules/Scripting/JsonStore/JsonStore.cs b/OpenSim/Region/OptionalModules/Scripting/JsonStore/JsonStore.cs
index c7f0001e06..088d0cdf88 100644
--- a/OpenSim/Region/OptionalModules/Scripting/JsonStore/JsonStore.cs
+++ b/OpenSim/Region/OptionalModules/Scripting/JsonStore/JsonStore.cs
@@ -93,6 +93,15 @@ namespace OpenSim.Region.OptionalModules.Scripting.JsonStore
         // extract the internals of a has reference
         protected static Regex m_HashPattern = new Regex("{([^}]+)}");
 
+        // -----------------------------------------------------------------
+        /// <summary>
+        /// This is a simple estimator for the size of the stored data, it
+        /// is not precise, but should be close enough to implement reasonable
+        /// limits on the storage space used
+        /// </summary>
+        // -----------------------------------------------------------------
+        public int StringSpace { get; set; }
+        
         // -----------------------------------------------------------------
         /// <summary>
         /// 
@@ -110,6 +119,7 @@ namespace OpenSim.Region.OptionalModules.Scripting.JsonStore
         // -----------------------------------------------------------------
         public JsonStore() 
         {
+            StringSpace = 0;
             m_TakeStore = new List<TakeValueCallbackClass>();
             m_ReadStore = new List<TakeValueCallbackClass>();
         }
@@ -247,6 +257,7 @@ namespace OpenSim.Region.OptionalModules.Scripting.JsonStore
             if (path.Count == 0)
             {
                 ValueStore = ovalue;
+                StringSpace = 0;
                 return true;
             }
 
@@ -278,8 +289,13 @@ namespace OpenSim.Region.OptionalModules.Scripting.JsonStore
                 {
                     string npkey = String.Format("[{0}]",amap.Count);
 
-                    amap.Add(ovalue);
-                    InvokeNextCallback(pexpr + npkey);
+                    if (ovalue != null)
+                    {
+                        StringSpace += ComputeSizeOf(ovalue);
+
+                        amap.Add(ovalue);
+                        InvokeNextCallback(pexpr + npkey);
+                    }
                     return true;
                 }
 
@@ -287,9 +303,14 @@ namespace OpenSim.Region.OptionalModules.Scripting.JsonStore
                 if (0 <= aval && aval < amap.Count)
                 {
                     if (ovalue == null)
+                    {
+                        StringSpace -= ComputeSizeOf(amap[aval]);
                         amap.RemoveAt(aval);
+                    }
                     else
                     {
+                        StringSpace -= ComputeSizeOf(amap[aval]);
+                        StringSpace += ComputeSizeOf(ovalue);
                         amap[aval] = ovalue;
                         InvokeNextCallback(pexpr + pkey);
                     }
@@ -313,6 +334,9 @@ namespace OpenSim.Region.OptionalModules.Scripting.JsonStore
                     OSDMap hmap = result as OSDMap;
                     if (ovalue != null)
                     {
+                        StringSpace -= ComputeSizeOf(hmap[hkey]);
+                        StringSpace += ComputeSizeOf(ovalue);
+                        
                         hmap[hkey] = ovalue;
                         InvokeNextCallback(pexpr + pkey);
                         return true;
@@ -321,6 +345,7 @@ namespace OpenSim.Region.OptionalModules.Scripting.JsonStore
                     // this is the remove case
                     if (hmap.ContainsKey(hkey))
                     {
+                        StringSpace -= ComputeSizeOf(hmap[hkey]);
                         hmap.Remove(hkey);
                         return true;
                     }
@@ -531,8 +556,27 @@ namespace OpenSim.Region.OptionalModules.Scripting.JsonStore
             
             return pkey;
         }
+
+        // -----------------------------------------------------------------
+        /// <summary>
+        /// 
+        /// </summary>
+        // -----------------------------------------------------------------
+        protected static int ComputeSizeOf(OSD value)
+        {
+            string sval;
+
+            if (ConvertOutputValue(value,out sval,true))
+                return sval.Length;
+
+            return 0;
+        }
     }
 
+    // -----------------------------------------------------------------
+    /// <summary>
+    /// </summary>
+    // -----------------------------------------------------------------
     public class JsonObjectStore : JsonStore
     {
         private static readonly ILog m_log =
@@ -566,6 +610,9 @@ namespace OpenSim.Region.OptionalModules.Scripting.JsonStore
         {
             m_scene = scene;
             m_objectID = oid;
+
+            // the size limit is imposed on whatever is already in the store
+            StringSpace = ComputeSizeOf(ValueStore);
         }
     }
     
diff --git a/OpenSim/Region/OptionalModules/Scripting/JsonStore/JsonStoreModule.cs b/OpenSim/Region/OptionalModules/Scripting/JsonStore/JsonStoreModule.cs
index 3249aa3216..f1ce856995 100644
--- a/OpenSim/Region/OptionalModules/Scripting/JsonStore/JsonStoreModule.cs
+++ b/OpenSim/Region/OptionalModules/Scripting/JsonStore/JsonStoreModule.cs
@@ -54,6 +54,9 @@ namespace OpenSim.Region.OptionalModules.Scripting.JsonStore
 
         private IConfig m_config = null;
         private bool m_enabled = false;
+        private bool m_enableObjectStore = false;
+        private int m_maxStringSpace = Int32.MaxValue;
+
         private Scene m_scene = null;
 
         private Dictionary<UUID,JsonStore> m_JsonValueStore;
@@ -90,6 +93,10 @@ namespace OpenSim.Region.OptionalModules.Scripting.JsonStore
                 }
 
                 m_enabled = m_config.GetBoolean("Enabled", m_enabled);
+                m_enableObjectStore = m_config.GetBoolean("EnableObjectStore", m_enableObjectStore);
+                m_maxStringSpace = m_config.GetInt("MaxStringSpace", m_maxStringSpace);
+                if (m_maxStringSpace == 0)
+                    m_maxStringSpace = Int32.MaxValue;
             }
             catch (Exception e)
             {
@@ -178,6 +185,7 @@ namespace OpenSim.Region.OptionalModules.Scripting.JsonStore
         public bool AttachObjectStore(UUID objectID)
         {
             if (! m_enabled) return false;
+            if (! m_enableObjectStore) return false;
 
             SceneObjectPart sop = m_scene.GetSceneObjectPart(objectID);
             if (sop == null)
@@ -311,7 +319,16 @@ namespace OpenSim.Region.OptionalModules.Scripting.JsonStore
             try
             {
                 lock (map)
+                {
+                    if (map.StringSpace > m_maxStringSpace)
+                    {
+                        m_log.WarnFormat("[JsonStore] {0} exceeded string size; {1} bytes used of {2} limit",
+                                         storeID,map.StringSpace,m_maxStringSpace);
+                        return false;
+                    }
+                    
                     return map.SetValue(path,value,useJson);
+                }
             }
             catch (Exception e)
             {
diff --git a/bin/OpenSimDefaults.ini b/bin/OpenSimDefaults.ini
index 7bdfd1ce30..2512428757 100644
--- a/bin/OpenSimDefaults.ini
+++ b/bin/OpenSimDefaults.ini
@@ -1652,6 +1652,10 @@
 [JsonStore]
 Enabled = False
 
+;; Enable direct access to the SOP dynamic attributes
+EnableObjectStore = False
+MaxStringSpace = 0
+
 ;;
 ;; These are defaults that are overwritten below in [Architecture].
 ;; These defaults allow OpenSim to work out of the box with