Replace a Multicast Delegate by a simple list of delegates in access Get

Can't seen more than one evocation on the multicast on this case, even expanding its evocation list (as it should be used in case one fails). With the list i
 do see what we want.

OpenSim/Services/Connectors/Asset/AssetServiceConnector.cs

@@ -55,7 +55,10 @@ namespace OpenSim.Services.Connectors
 
         // Keeps track of concurrent requests for the same asset, so that it's only loaded once.
         // Maps: Asset ID -> Handlers which will be called when the asset has been loaded
-        private Dictionary<string, AssetRetrievedEx> m_AssetHandlers = new Dictionary<string, AssetRetrievedEx>();
+//        private Dictionary<string, AssetRetrievedEx> m_AssetHandlers = new Dictionary<string, AssetRetrievedEx>();
+
+        private Dictionary<string, List<AssetRetrievedEx>> m_AssetHandlers = new Dictionary<string, List<AssetRetrievedEx>>();
+
         private Dictionary<string, string> m_UriMap = new Dictionary<string, string>();
 
         public AssetServicesConnector()
@@ -269,16 +272,21 @@ namespace OpenSim.Services.Connectors
                 {
                     AssetRetrievedEx handlerEx = new AssetRetrievedEx(delegate(AssetBase _asset) { handler(id, sender, _asset); });
 
-                    AssetRetrievedEx handlers;
+//                    AssetRetrievedEx handlers;
+                    List<AssetRetrievedEx> handlers;
                     if (m_AssetHandlers.TryGetValue(id, out handlers))
                     {
                         // Someone else is already loading this asset. It will notify our handler when done.
-                        handlers += handlerEx;
+//                        handlers += handlerEx;
+                        handlers.Add(handlerEx);
                         return true;
                     }
 
                     // Load the asset ourselves
-                    handlers += handlerEx;
+//                    handlers += handlerEx;
+                    handlers = new List<AssetRetrievedEx>();
+                    handlers.Add(handlerEx);
+
                     m_AssetHandlers.Add(id, handlers);
                 }
 
@@ -290,14 +298,24 @@ namespace OpenSim.Services.Connectors
                         {
                             if (m_Cache != null)
                                 m_Cache.Cache(a);
-
+/*
                             AssetRetrievedEx handlers;
                             lock (m_AssetHandlers)
                             {
                                 handlers = m_AssetHandlers[id];
                                 m_AssetHandlers.Remove(id);
                             }
+
                             handlers.Invoke(a);
+*/
+                            List<AssetRetrievedEx> handlers;
+                            lock (m_AssetHandlers)
+                            {
+                                handlers = m_AssetHandlers[id];
+                                m_AssetHandlers.Remove(id);
+                            }
+                            foreach (AssetRetrievedEx h in handlers)
+                                h.Invoke(a);
                         });
                     
                     success = true;