diff --git a/OpenMetaverse/AssetManager.cs b/OpenMetaverse/AssetManager.cs
index ab6bc4da..44f4ee4f 100644
--- a/OpenMetaverse/AssetManager.cs
+++ b/OpenMetaverse/AssetManager.cs
@@ -282,7 +282,7 @@ namespace OpenMetaverse
             Priority = priority;
             DiscardLevel = discardLevel;
         }
-        
+
     }
     #endregion Transfer Classes
 
@@ -295,61 +295,147 @@ namespace OpenMetaverse
         const int TRANSFER_HEADER_TIMEOUT = 1000 * 15;
 
         #region Delegates
-
         /// <summary>
-        /// 
+        /// Callback used for various asset download requests
         /// </summary>
-        /// <param name="transfer"></param>
-        /// <param name="asset"></param>
+        /// <param name="transfer">Transfer information</param>
+        /// <param name="asset">Downloaded asset, null on fail</param>
         public delegate void AssetReceivedCallback(AssetDownload transfer, Asset asset);
         /// <summary>
-        /// 
+        /// Callback used upon competition of baked texture upload
         /// </summary>
-        /// <param name="xfer"></param>
-        public delegate void XferReceivedCallback(XferDownload xfer);
-        /// <summary>
-        /// 
-        /// </summary>
-        /// <param name="upload"></param>
-        public delegate void AssetUploadedCallback(AssetUpload upload);
-        /// <summary>
-        /// 
-        /// </summary>
-        /// <param name="newAssetID"></param>
+        /// <param name="newAssetID">Asset UUID of the newly uploaded baked texture</param>
         public delegate void BakedTextureUploadedCallback(UUID newAssetID);
-        /// <summary>
-        /// 
-        /// </summary>
-        /// <param name="upload"></param>
-        public delegate void UploadProgressCallback(AssetUpload upload);
-        /// <summary>
-        /// Callback fired when an InitiateDownload packet is received
-        /// </summary>
-        /// <param name="simFilename">The filename on the simulator</param>
-        /// <param name="viewerFilename">The name of the file the viewer requested</param>
-        public delegate void InitiateDownloadCallback(string simFilename, string viewerFilename);
-        /// <summary>
-        /// Fired when a texture is in the process of being downloaded by the TexturePipeline class
-        /// </summary>
-        /// <param name="imageID">The asset textures <see cref="UUID"/></param>
-        /// <param name="recieved">The total number of bytes received</param>
-        /// <param name="total">The total number of bytes expected</param>
-        public delegate void ImageReceiveProgressCallback(UUID imageID, int recieved, int total);
-        
+
         #endregion Delegates
 
         #region Events
 
-        /// <summary></summary>
-        public event XferReceivedCallback OnXferReceived;
-        /// <summary></summary>
-        public event AssetUploadedCallback OnAssetUploaded;
-        /// <summary></summary>
-        public event UploadProgressCallback OnUploadProgress;
+        #region XferReceived
+        /// <summary>The event subscribers. null if no subcribers</summary>
+        private EventHandler<XferReceivedEventArgs> m_XferReceivedEvent;
+
+        /// <summary>Raises the XferReceived event</summary>
+        /// <param name="e">A XferReceivedEventArgs object containing the
+        /// data returned from the simulator</param>
+        protected virtual void OnXferReceived(XferReceivedEventArgs e)
+        {
+            EventHandler<XferReceivedEventArgs> handler = m_XferReceivedEvent;
+            if (handler != null)
+                handler(this, e);
+        }
+
+        /// <summary>Thread sync lock object</summary>
+        private readonly object m_XferReceivedLock = new object();
+
+        /// <summary>Raised when the simulator responds sends </summary>
+        public event EventHandler<XferReceivedEventArgs> XferReceived
+        {
+            add { lock (m_XferReceivedLock) { m_XferReceivedEvent += value; } }
+            remove { lock (m_XferReceivedLock) { m_XferReceivedEvent -= value; } }
+        }
+        #endregion
+
+        #region AssetUploaded
+        /// <summary>The event subscribers. null if no subcribers</summary>
+        private EventHandler<AssetUploadEventArgs> m_AssetUploadedEvent;
+
+        /// <summary>Raises the AssetUploaded event</summary>
+        /// <param name="e">A AssetUploadedEventArgs object containing the
+        /// data returned from the simulator</param>
+        protected virtual void OnAssetUploaded(AssetUploadEventArgs e)
+        {
+            EventHandler<AssetUploadEventArgs> handler = m_AssetUploadedEvent;
+            if (handler != null)
+                handler(this, e);
+        }
+
+        /// <summary>Thread sync lock object</summary>
+        private readonly object m_AssetUploadedLock = new object();
+
+        /// <summary>Raised during upload completes</summary>
+        public event EventHandler<AssetUploadEventArgs> AssetUploaded
+        {
+            add { lock (m_AssetUploadedLock) { m_AssetUploadedEvent += value; } }
+            remove { lock (m_AssetUploadedLock) { m_AssetUploadedEvent -= value; } }
+        }
+        #endregion
+
+        #region UploadProgress
+        /// <summary>The event subscribers. null if no subcribers</summary>
+        private EventHandler<AssetUploadEventArgs> m_UploadProgressEvent;
+
+        /// <summary>Raises the UploadProgress event</summary>
+        /// <param name="e">A UploadProgressEventArgs object containing the
+        /// data returned from the simulator</param>
+        protected virtual void OnUploadProgress(AssetUploadEventArgs e)
+        {
+            EventHandler<AssetUploadEventArgs> handler = m_UploadProgressEvent;
+            if (handler != null)
+                handler(this, e);
+        }
+
+        /// <summary>Thread sync lock object</summary>
+        private readonly object m_UploadProgressLock = new object();
+
+        /// <summary>Raised during upload with progres update</summary>
+        public event EventHandler<AssetUploadEventArgs> UploadProgress
+        {
+            add { lock (m_UploadProgressLock) { m_UploadProgressEvent += value; } }
+            remove { lock (m_UploadProgressLock) { m_UploadProgressEvent -= value; } }
+        }
+        #endregion UploadProgress
+
+        #region InitiateDownload
+        /// <summary>The event subscribers. null if no subcribers</summary>
+        private EventHandler<InitiateDownloadEventArgs> m_InitiateDownloadEvent;
+
+        /// <summary>Raises the InitiateDownload event</summary>
+        /// <param name="e">A InitiateDownloadEventArgs object containing the
+        /// data returned from the simulator</param>
+        protected virtual void OnInitiateDownload(InitiateDownloadEventArgs e)
+        {
+            EventHandler<InitiateDownloadEventArgs> handler = m_InitiateDownloadEvent;
+            if (handler != null)
+                handler(this, e);
+        }
+
+        /// <summary>Thread sync lock object</summary>
+        private readonly object m_InitiateDownloadLock = new object();
+
         /// <summary>Fired when the simulator sends an InitiateDownloadPacket, used to download terrain .raw files</summary>
-        public event InitiateDownloadCallback OnInitiateDownload;
-        /// <summary>Fired when during texture downloads to indicate the progress of the download</summary>
-        public event ImageReceiveProgressCallback OnImageRecieveProgress;
+        public event EventHandler<InitiateDownloadEventArgs> InitiateDownload
+        {
+            add { lock (m_InitiateDownloadLock) { m_InitiateDownloadEvent += value; } }
+            remove { lock (m_InitiateDownloadLock) { m_InitiateDownloadEvent -= value; } }
+        }
+        #endregion InitiateDownload
+
+        #region ImageReceiveProgress
+        /// <summary>The event subscribers. null if no subcribers</summary>
+        private EventHandler<ImageReceiveProgressEventArgs> m_ImageReceiveProgressEvent;
+
+        /// <summary>Raises the ImageReceiveProgress event</summary>
+        /// <param name="e">A ImageReceiveProgressEventArgs object containing the
+        /// data returned from the simulator</param>
+        protected virtual void OnImageReceiveProgress(ImageReceiveProgressEventArgs e)
+        {
+            EventHandler<ImageReceiveProgressEventArgs> handler = m_ImageReceiveProgressEvent;
+            if (handler != null)
+                handler(this, e);
+        }
+
+        /// <summary>Thread sync lock object</summary>
+        private readonly object m_ImageReceiveProgressLock = new object();
+
+        /// <summary>Fired when a texture is in the process of being downloaded by the TexturePipeline class</summary>
+        public event EventHandler<ImageReceiveProgressEventArgs> ImageReceiveProgress
+        {
+            add { lock (m_ImageReceiveProgressLock) { m_ImageReceiveProgressEvent += value; } }
+            remove { lock (m_ImageReceiveProgressLock) { m_ImageReceiveProgressEvent -= value; } }
+        }
+        #endregion ImageReceiveProgress
+
         #endregion Events
 
         /// <summary>Texture download cache</summary>
@@ -364,7 +450,7 @@ namespace OpenMetaverse
         private AssetUpload PendingUpload;
         private object PendingUploadLock = new object();
         private volatile bool WaitingForUploadConfirm = false;
-        
+
         /// <summary>
         /// Default constructor
         /// </summary>
@@ -392,7 +478,7 @@ namespace OpenMetaverse
             Client.Network.RegisterCallback(PacketType.InitiateDownload, InitiateDownloadPacketHandler);
 
         }
-        
+
         /// <summary>
         /// Request an asset download
         /// </summary>
@@ -557,7 +643,7 @@ namespace OpenMetaverse
 
                 try { callback(transfer, asset); }
                 catch (Exception e) { Logger.Log(e.Message, Helpers.LogLevel.Error, Client, e); }
-                
+
                 return;
             }
 
@@ -600,7 +686,7 @@ namespace OpenMetaverse
         /// <param name="assetData">An AssetUpload object containing the data to upload to the simulator</param>
         internal void SetPendingAssetUploadData(AssetUpload assetData)
         {
-            lock(PendingUploadLock)
+            lock (PendingUploadLock)
                 PendingUpload = assetData;
         }
 
@@ -622,7 +708,7 @@ namespace OpenMetaverse
             asset.AssetID = assetID;
             return transferID;
         }
-        
+
         /// <summary>
         /// Request an asset be uploaded to the simulator
         /// </summary>
@@ -649,10 +735,10 @@ namespace OpenMetaverse
         /// <returns>The <seealso cref="UUID"/> of the transfer, can be used to correlate the upload with
         /// events being fired</returns>
         public UUID RequestUpload(out UUID assetID, AssetType type, byte[] data, bool storeLocal)
-		{
-			return RequestUpload(out assetID, type, data, storeLocal, UUID.Random());
-		}
-		
+        {
+            return RequestUpload(out assetID, type, data, storeLocal, UUID.Random());
+        }
+
         /// <summary>
         /// Initiate an asset upload
         /// </summary>
@@ -673,8 +759,8 @@ namespace OpenMetaverse
             upload.AssetID = assetID;
             upload.Size = data.Length;
             upload.XferID = 0;
-			upload.ID = transactionID;
-			
+            upload.ID = transactionID;
+
             // Build and send the upload packet
             AssetUploadRequestPacket request = new AssetUploadRequestPacket();
             request.AssetBlock.StoreLocal = storeLocal;
@@ -688,8 +774,8 @@ namespace OpenMetaverse
                     String.Format("Beginning asset upload [Single Packet], ID: {0}, AssetID: {1}, Size: {2}",
                     upload.ID.ToString(), upload.AssetID.ToString(), upload.Size), Helpers.LogLevel.Info, Client);
 
-                    Transfers[upload.ID]=upload;         
-                
+                Transfers[upload.ID] = upload;
+
                 // The whole asset will fit in this packet, makes things easy
                 request.AssetBlock.AssetData = data;
                 upload.Transferred = data.Length;
@@ -798,17 +884,17 @@ namespace OpenMetaverse
                         UUID transactionID = UUID.Random();
                         BakedTextureUploadedCallback uploadCallback = (BakedTextureUploadedCallback)o;
                         AutoResetEvent uploadEvent = new AutoResetEvent(false);
-                        AssetUploadedCallback udpCallback =
-                            delegate(AssetUpload upload)
+                        EventHandler<AssetUploadEventArgs> udpCallback =
+                            delegate(object sender, AssetUploadEventArgs e)
                             {
-                                if (upload.ID == transactionID)
+                                if (e.Upload.ID == transactionID)
                                 {
                                     uploadEvent.Set();
-                                    uploadCallback(upload.Success ? upload.AssetID : UUID.Zero);
+                                    uploadCallback(e.Upload.Success ? e.Upload.AssetID : UUID.Zero);
                                 }
                             };
 
-                        OnAssetUploaded += udpCallback;
+                        AssetUploaded += udpCallback;
 
                         UUID assetID;
                         bool success;
@@ -823,7 +909,7 @@ namespace OpenMetaverse
                             success = false;
                         }
 
-                        OnAssetUploaded -= udpCallback;
+                        AssetUploaded -= udpCallback;
 
                         if (!success)
                             uploadCallback(UUID.Zero);
@@ -902,9 +988,9 @@ namespace OpenMetaverse
         /// }
         /// </code>
         /// </example>
-        public void RequestImage(UUID textureID, ImageType imageType, float priority, int discardLevel, 
+        public void RequestImage(UUID textureID, ImageType imageType, float priority, int discardLevel,
             uint packetStart, TextureDownloadCallback callback, bool progress)
-        {            
+        {
             Texture.RequestTexture(textureID, imageType, priority, discardLevel, packetStart, callback, progress);
         }
 
@@ -968,11 +1054,8 @@ namespace OpenMetaverse
         /// <param name="totalBytes">the total number of bytes expected</param>
         internal void FireImageProgressEvent(UUID texureID, int transferredBytes, int totalBytes)
         {
-            if (OnImageRecieveProgress != null)
-            {
-                try { OnImageRecieveProgress(texureID, transferredBytes, totalBytes); }
-                catch (Exception e) { Logger.Log(e.Message, Helpers.LogLevel.Error, Client, e); }
-            }
+            try { OnImageReceiveProgress(new ImageReceiveProgressEventArgs(texureID, transferredBytes, totalBytes)); }
+            catch (Exception e) { Logger.Log(e.Message, Helpers.LogLevel.Error, Client, e); }
         }
 
         #region Helpers
@@ -1266,13 +1349,13 @@ namespace OpenMetaverse
         /// <param name="e">The EventArgs object containing the packet data</param>
         protected void InitiateDownloadPacketHandler(object sender, PacketReceivedEventArgs e)
         {
-            if (OnInitiateDownload != null)
+            InitiateDownloadPacket request = (InitiateDownloadPacket)e.Packet;
+            try
             {
-                InitiateDownloadPacket request = (InitiateDownloadPacket)e.Packet;
-                try { OnInitiateDownload(Utils.BytesToString(request.FileData.SimFilename), 
-                    Utils.BytesToString(request.FileData.ViewerFilename)); }
-                catch (Exception ex) { Logger.Log(ex.Message, Helpers.LogLevel.Error, Client, ex); }
-            }            
+                OnInitiateDownload(new InitiateDownloadEventArgs(Utils.BytesToString(request.FileData.SimFilename),
+                    Utils.BytesToString(request.FileData.ViewerFilename)));
+            }
+            catch (Exception ex) { Logger.Log(ex.Message, Helpers.LogLevel.Error, Client, ex); }
         }
 
         /// <summary>Process an incoming packet and raise the appropriate events</summary>
@@ -1320,11 +1403,8 @@ namespace OpenMetaverse
                 //Client.DebugLog(String.Format("ACK for upload {0} of asset type {1} ({2}/{3})",
                 //    upload.AssetID.ToString(), upload.Type, upload.Transferred, upload.Size));
 
-                if (OnUploadProgress != null)
-                {
-                    try { OnUploadProgress(upload); }
-                    catch (Exception ex) { Logger.Log(ex.Message, Helpers.LogLevel.Error, Client, ex); }
-                }
+                try { OnUploadProgress(new AssetUploadEventArgs(upload)); }
+                catch (Exception ex) { Logger.Log(ex.Message, Helpers.LogLevel.Error, Client, ex); }
 
                 if (upload.Transferred < upload.Size)
                     SendNextUploadPacket(upload);
@@ -1342,7 +1422,7 @@ namespace OpenMetaverse
             // will never be called so we need to set this here as well
             WaitingForUploadConfirm = false;
 
-            if (OnAssetUploaded != null)
+            if (m_AssetUploadedEvent != null)
             {
                 bool found = false;
                 KeyValuePair<UUID, Transfer> foundTransfer = new KeyValuePair<UUID, Transfer>();
@@ -1372,7 +1452,7 @@ namespace OpenMetaverse
                 {
                     lock (Transfers) Transfers.Remove(foundTransfer.Key);
 
-                    try { OnAssetUploaded((AssetUpload)foundTransfer.Value); }
+                    try { OnAssetUploaded(new AssetUploadEventArgs((AssetUpload)foundTransfer.Value)); }
                     catch (Exception ex) { Logger.Log(ex.Message, Helpers.LogLevel.Error, Client, ex); }
                 }
                 else
@@ -1459,11 +1539,8 @@ namespace OpenMetaverse
                     download.Success = true;
                     lock (Transfers) Transfers.Remove(download.ID);
 
-                    if (OnXferReceived != null)
-                    {
-                        try { OnXferReceived(download); }
-                        catch (Exception ex) { Logger.Log(ex.Message, Helpers.LogLevel.Error, Client, ex); }
-                    }
+                    try { OnXferReceived(new XferReceivedEventArgs(download)); }
+                    catch (Exception ex) { Logger.Log(ex.Message, Helpers.LogLevel.Error, Client, ex); }
                 }
             }
         }
@@ -1489,16 +1566,88 @@ namespace OpenMetaverse
                 }
             }
 
-            if (download != null && OnXferReceived != null)
+            if (download != null && m_XferReceivedEvent != null)
             {
                 download.Success = false;
                 download.Error = (TransferError)abort.XferID.Result;
 
-                try { OnXferReceived(download); }
+                try { OnXferReceived(new XferReceivedEventArgs(download)); }
                 catch (Exception ex) { Logger.Log(ex.Message, Helpers.LogLevel.Error, Client, ex); }
             }
         }
 
         #endregion Xfer Callbacks
     }
+    #region EventArg classes
+    // <summary>Provides data for XferReceived event</summary>
+    public class XferReceivedEventArgs : EventArgs
+    {
+        private readonly XferDownload m_Xfer;
+
+        /// <summary>Xfer data</summary>
+        public XferDownload Xfer { get { return m_Xfer; } }
+
+        public XferReceivedEventArgs(XferDownload xfer)
+        {
+            this.m_Xfer = xfer;
+        }
+    }
+
+    // <summary>Provides data for AssetUploaded event</summary>
+    public class AssetUploadEventArgs : EventArgs
+    {
+        private readonly AssetUpload m_Upload;
+
+        /// <summary>Upload data</summary>
+        public AssetUpload Upload { get { return m_Upload; } }
+
+        public AssetUploadEventArgs(AssetUpload upload)
+        {
+            this.m_Upload = upload;
+        }
+    }
+
+    // <summary>Provides data for InitiateDownloaded event</summary>
+    public class InitiateDownloadEventArgs : EventArgs
+    {
+        private readonly string m_SimFileName;
+        private readonly string m_ViewerFileName;
+
+        /// <summary>Filename used on the simulator</summary>
+        public string SimFileName { get { return m_SimFileName; } }
+
+        /// <summary>Filename used by the client</summary>
+        public string ViewerFileName { get { return m_ViewerFileName; } }
+
+        public InitiateDownloadEventArgs(string simFilename, string viewerFilename)
+        {
+            this.m_SimFileName = simFilename;
+            this.m_ViewerFileName = viewerFilename;
+        }
+    }
+
+    // <summary>Provides data for ImageReceiveProgress event</summary>
+    public class ImageReceiveProgressEventArgs : EventArgs
+    {
+        private readonly UUID m_ImageID;
+        private readonly int m_Received;
+        private readonly int m_Total;
+
+        /// <summary>UUID of the image that is in progress</summary>
+        public UUID ImageID { get { return m_ImageID; } }
+
+        /// <summary>Number of bytes received so far</summary>
+        public int Received { get { return m_Received; } }
+
+        /// <summary>Image size in bytes</summary>
+        public int Total { get { return m_Total; } }
+
+        public ImageReceiveProgressEventArgs(UUID imageID, int received, int total)
+        {
+            this.m_ImageID = imageID;
+            this.m_Received = received;
+            this.m_Total = total;
+        }
+    }
+    #endregion
 }
diff --git a/OpenMetaverse/InventoryManager.cs b/OpenMetaverse/InventoryManager.cs
index 428753a3..6fa41ffc 100644
--- a/OpenMetaverse/InventoryManager.cs
+++ b/OpenMetaverse/InventoryManager.cs
@@ -2839,24 +2839,24 @@ namespace OpenMetaverse
                     ulong xferID = 0;
                     AutoResetEvent taskDownloadEvent = new AutoResetEvent(false);
 
-                    AssetManager.XferReceivedCallback xferCallback =
-                        delegate(XferDownload xfer)
+                    EventHandler<XferReceivedEventArgs> xferCallback =
+                        delegate(object sender, XferReceivedEventArgs e)
                         {
-                            if (xfer.XferID == xferID)
+                            if (e.Xfer.XferID == xferID)
                             {
-                                assetData = xfer.AssetData;
+                                assetData = e.Xfer.AssetData;
                                 taskDownloadEvent.Set();
                             }
                         };
 
-                    Client.Assets.OnXferReceived += xferCallback;
+                    Client.Assets.XferReceived += xferCallback;
 
                     // Start the actual asset xfer
                     xferID = Client.Assets.RequestAssetXfer(filename, true, false, UUID.Zero, AssetType.Unknown, true);
 
                     if (taskDownloadEvent.WaitOne(timeoutMS, false))
                     {
-                        Client.Assets.OnXferReceived -= xferCallback;
+                        Client.Assets.XferReceived -= xferCallback;
 
                         String taskList = Utils.BytesToString(assetData);
                         return ParseTaskInventory(taskList);
@@ -2864,7 +2864,7 @@ namespace OpenMetaverse
                     else
                     {
                         Logger.Log("Timed out waiting for task inventory download for " + filename, Helpers.LogLevel.Warning, Client);
-                        Client.Assets.OnXferReceived -= xferCallback;
+                        Client.Assets.XferReceived -= xferCallback;
                         return null;
                     }
                 }
diff --git a/Programs/PrimWorkshop/frmBrowser.cs b/Programs/PrimWorkshop/frmBrowser.cs
index 63022938..bfb97ef8 100644
--- a/Programs/PrimWorkshop/frmBrowser.cs
+++ b/Programs/PrimWorkshop/frmBrowser.cs
@@ -160,12 +160,11 @@ namespace PrimWorkshop
             Client.Network.LoginProgress += Network_OnLogin;
             Client.Network.Disconnected += Network_OnDisconnected;
             Client.Network.SimChanged += Network_OnCurrentSimChanged;
-            Client.Network.EventQueueRunning += Network_OnEventQueueRunning;            
+            Client.Network.EventQueueRunning += Network_OnEventQueueRunning;
             Client.Objects.ObjectUpdate += Objects_OnNewPrim;
             Client.Terrain.LandPatchReceived += new EventHandler<LandPatchReceivedEventArgs>(Terrain_LandPatchReceived);
             Client.Parcels.SimParcelsDownloaded += new EventHandler<SimParcelsDownloadedEventArgs>(Parcels_SimParcelsDownloaded);
-
-            Client.Assets.OnImageRecieveProgress += new AssetManager.ImageReceiveProgressCallback(Assets_OnImageRecieveProgress);
+            Client.Assets.ImageReceiveProgress += new EventHandler<ImageReceiveProgressEventArgs>(Assets_ImageReceiveProgress);
             // Initialize the camera object
             InitCamera();
 
@@ -317,7 +316,7 @@ namespace PrimWorkshop
             // Build a list of primitives (parent+children) to export
             List<Primitive> primList = new List<Primitive>();
             primList.Add(parent.Prim);
-            
+
             lock (RenderPrimList)
             {
                 foreach (RenderablePrim render in RenderPrimList.Values)
@@ -351,7 +350,7 @@ namespace PrimWorkshop
             List<UUID> textureList = new List<UUID>();
             prims = 0;
             textures = 0;
-            
+
             // Write the LLSD to the hard drive in XML format
             string output = OSDParser.SerializeLLSDXmlString(Helpers.PrimListToOSD(primList));
             try
@@ -992,7 +991,7 @@ namespace PrimWorkshop
                 // Texture for this face
                 if (teFace.TextureID != UUID.Zero &&
                     teFace.TextureID != Primitive.TextureEntry.WHITE_TEXTURE)
-                { 
+                {
                     lock (Textures)
                     {
                         if (!Textures.ContainsKey(teFace.TextureID))
@@ -1058,7 +1057,7 @@ namespace PrimWorkshop
         private void Network_OnCurrentSimChanged(object sender, SimChangedEventArgs e)
         {
             Console.WriteLine("CurrentSim set to " + Client.Network.CurrentSim + ", downloading parcel information");
-            
+
             BeginInvoke((MethodInvoker)delegate() { txtSim.Text = Client.Network.CurrentSim.Name; });
 
             //InitHeightmap();
@@ -1261,7 +1260,7 @@ namespace PrimWorkshop
                     Gl.glDisable(Gl.GL_BLEND);
                     Gl.glEnable(Gl.GL_DEPTH_TEST);
 
-StartRender:
+                StartRender:
 
                     foreach (RenderablePrim render in RenderPrimList.Values)
                     {
@@ -1398,7 +1397,7 @@ StartRender:
                         Gl.glPopMatrix();
                     }
                 );
-                
+
                 Gl.glColor3f(1f, 1f, 1f);
             }
         }
@@ -1410,7 +1409,7 @@ StartRender:
             bool alpha = false;
             ManagedImage imgData = null;
             byte[] raw = null;
-            
+
             bool success = (state == TextureRequestState.Finished);
 
             UUID id = asset.AssetID;
@@ -1497,21 +1496,21 @@ StartRender:
                 Console.WriteLine(ex);
             }
         }
-        
-        private void Assets_OnImageRecieveProgress(UUID imageID, int recieved, int total)
+
+        private void Assets_ImageReceiveProgress(object sender, ImageReceiveProgressEventArgs e)
         {
             lock (DownloadList)
             {
                 GlacialComponents.Controls.GLItem item;
-                if (DownloadList.TryGetValue(imageID, out item))
+                if (DownloadList.TryGetValue(e.ImageID, out item))
                 {
                     // Update an existing item
                     BeginInvoke(
                         (MethodInvoker)delegate()
                         {
                             ProgressBar prog = (ProgressBar)item.SubItems[1].Control;
-                            if (total >= recieved)
-                                prog.Value = (int)Math.Round((((double)recieved / (double)total) * 100.0d));
+                            if (e.Total >= e.Received)
+                                prog.Value = (int)Math.Round((((double)e.Received / (double)e.Total) * 100.0d));
                         });
                 }
                 else
@@ -1520,17 +1519,17 @@ StartRender:
                     ProgressBar prog = new ProgressBar();
                     prog.Minimum = 0;
                     prog.Maximum = 100;
-                    if (total >= recieved)
-                        prog.Value = (int)Math.Round((((double)recieved / (double)total) * 100.0d));
+                    if (e.Total >= e.Received)
+                        prog.Value = (int)Math.Round((((double)e.Received / (double)e.Total) * 100.0d));
                     else
                         prog.Value = 0;
 
                     // List item
                     item = new GlacialComponents.Controls.GLItem();
-                    item.SubItems[0].Text = imageID.ToString();
+                    item.SubItems[0].Text = e.ImageID.ToString();
                     item.SubItems[1].Control = prog;
 
-                    DownloadList[imageID] = item;
+                    DownloadList[e.ImageID] = item;
 
                     BeginInvoke(
                         (MethodInvoker)delegate()
@@ -1673,7 +1672,7 @@ StartRender:
         {
             if (Pivoting)
             {
-                float a,x,y,z;
+                float a, x, y, z;
 
                 Control control = (Control)sender;
                 Point mouse = control.PointToScreen(new Point(e.X, e.Y));
diff --git a/Programs/examples/TestClient/Commands/Estate/DownloadTerrainCommand.cs b/Programs/examples/TestClient/Commands/Estate/DownloadTerrainCommand.cs
index e594bb36..019e2105 100644
--- a/Programs/examples/TestClient/Commands/Estate/DownloadTerrainCommand.cs
+++ b/Programs/examples/TestClient/Commands/Estate/DownloadTerrainCommand.cs
@@ -17,7 +17,7 @@ namespace OpenMetaverse.TestClient
         /// Create a Synchronization event object
         /// </summary>
         private static AutoResetEvent xferTimeout = new AutoResetEvent(false);
-        
+
         /// <summary>A string we use to report the result of the request with.</summary>
         private static System.Text.StringBuilder result = new System.Text.StringBuilder();
 
@@ -44,21 +44,22 @@ namespace OpenMetaverse.TestClient
         {
             int timeout = 120000; // default the timeout to 2 minutes
             fileName = Client.Network.CurrentSim.Name + ".raw";
-            
-            if(args.Length > 0 && int.TryParse(args[0], out timeout) != true)
+
+            if (args.Length > 0 && int.TryParse(args[0], out timeout) != true)
                 return "Usage: downloadterrain [timeout]";
-            
+
             // Create a delegate which will be fired when the simulator receives our download request
             // Starts the actual transfer request
-            AssetManager.InitiateDownloadCallback initiateDownloadDelegate = delegate(string simFilename, string viewerFileName) {
-                Client.Assets.RequestAssetXfer(simFilename, false, false, UUID.Zero, AssetType.Unknown, false);
-            };
+            EventHandler<InitiateDownloadEventArgs> initiateDownloadDelegate =
+                delegate(object sender, InitiateDownloadEventArgs e)
+                {
+                    Client.Assets.RequestAssetXfer(e.SimFileName, false, false, UUID.Zero, AssetType.Unknown, false);
+                };
 
             // Subscribe to the event that will tell us the status of the download
-            Client.Assets.OnXferReceived += new AssetManager.XferReceivedCallback(Assets_OnXferReceived);
-
+            Client.Assets.XferReceived += new EventHandler<XferReceivedEventArgs>(Assets_XferReceived);
             // subscribe to the event which tells us when the simulator has received our request
-            Client.Assets.OnInitiateDownload += initiateDownloadDelegate;
+            Client.Assets.InitiateDownload += initiateDownloadDelegate;
 
             // configure request to tell the simulator to send us the file
             List<string> parameters = new List<string>();
@@ -74,8 +75,8 @@ namespace OpenMetaverse.TestClient
             }
 
             // unsubscribe from events
-            Client.Assets.OnInitiateDownload -= initiateDownloadDelegate;
-            Client.Assets.OnXferReceived -= new AssetManager.XferReceivedCallback(Assets_OnXferReceived);
+            Client.Assets.InitiateDownload -= initiateDownloadDelegate;
+            Client.Assets.XferReceived -= new EventHandler<XferReceivedEventArgs>(Assets_XferReceived);
 
             // return the result
             return result.ToString();
@@ -84,23 +85,21 @@ namespace OpenMetaverse.TestClient
         /// <summary>
         /// Handle the reply to the OnXferReceived event
         /// </summary>
-        /// <param name="xfer"></param>
-        private void Assets_OnXferReceived(XferDownload xfer)
+        private void Assets_XferReceived(object sender, XferReceivedEventArgs e)
         {
-            if (xfer.Success)
+            if (e.Xfer.Success)
             {
                 // set the result message
-                result.AppendFormat("Terrain file {0} ({1} bytes) downloaded successfully, written to {2}", xfer.Filename, xfer.Size, fileName);
+                result.AppendFormat("Terrain file {0} ({1} bytes) downloaded successfully, written to {2}", e.Xfer.Filename, e.Xfer.Size, fileName);
 
                 // write the file to disk
                 FileStream stream = new FileStream(fileName, FileMode.Create);
                 BinaryWriter w = new BinaryWriter(stream);
-                w.Write(xfer.AssetData);
+                w.Write(e.Xfer.AssetData);
                 w.Close();
 
                 // tell the application we've gotten the file
                 xferTimeout.Set();
-
             }
         }
     }
diff --git a/Programs/examples/TestClient/Commands/Estate/UploadRawTerrainCommand.cs b/Programs/examples/TestClient/Commands/Estate/UploadRawTerrainCommand.cs
index 904c0c63..7a0be306 100644
--- a/Programs/examples/TestClient/Commands/Estate/UploadRawTerrainCommand.cs
+++ b/Programs/examples/TestClient/Commands/Estate/UploadRawTerrainCommand.cs
@@ -33,8 +33,7 @@ namespace OpenMetaverse.TestClient
 
             // Setup callbacks for upload request reply and progress indicator 
             // so we can detect when the upload is complete
-            Client.Assets.OnUploadProgress += new AssetManager.UploadProgressCallback(Assets_OnUploadProgress);
-
+            Client.Assets.UploadProgress += new EventHandler<AssetUploadEventArgs>(Assets_UploadProgress);
             byte[] fileData = File.ReadAllBytes(fileName);
 
             Client.Estate.UploadTerrain(fileData, fileName);
@@ -57,17 +56,13 @@ namespace OpenMetaverse.TestClient
         /// </summary>
         private void Cleanup()
         {
-            Client.Assets.OnUploadProgress -= new AssetManager.UploadProgressCallback(Assets_OnUploadProgress);
+            Client.Assets.UploadProgress -= new EventHandler<AssetUploadEventArgs>(Assets_UploadProgress);
         }
 
 
-        /// <summary>
-        /// 
-        /// </summary>
-        /// <param name="upload"></param>
-        void Assets_OnUploadProgress(AssetUpload upload)
+        void Assets_UploadProgress(object sender, AssetUploadEventArgs e)
         {
-            if (upload.Transferred == upload.Size)
+            if (e.Upload.Transferred == e.Upload.Size)
             {
                 WaitForUploadComplete.Set();
             }
diff --git a/Programs/examples/TestClient/Commands/Inventory/XferCommand.cs b/Programs/examples/TestClient/Commands/Inventory/XferCommand.cs
index c5d0a55d..50292758 100644
--- a/Programs/examples/TestClient/Commands/Inventory/XferCommand.cs
+++ b/Programs/examples/TestClient/Commands/Inventory/XferCommand.cs
@@ -52,25 +52,25 @@ namespace OpenMetaverse.TestClient
             ulong xferID = 0;
             byte[] data = null;
 
-            AssetManager.XferReceivedCallback xferCallback =
-                delegate(XferDownload xfer)
+            EventHandler<XferReceivedEventArgs> xferCallback =
+                delegate(object sender, XferReceivedEventArgs e)
                 {
-                    if (xfer.XferID == xferID)
+                    if (e.Xfer.XferID == xferID)
                     {
-                        if (xfer.Success)
-                            data = xfer.AssetData;
+                        if (e.Xfer.Success)
+                            data = e.Xfer.AssetData;
                         xferEvent.Set();
                     }
                 };
 
-            Client.Assets.OnXferReceived += xferCallback;
+            Client.Assets.XferReceived += xferCallback;
 
             filename = assetID + ".asset";
             xferID = Client.Assets.RequestAssetXfer(filename, false, true, assetID, type, false);
 
             xferEvent.WaitOne(FETCH_ASSET_TIMEOUT, false);
 
-            Client.Assets.OnXferReceived -= xferCallback;
+            Client.Assets.XferReceived -= xferCallback;
 
             return data;
         }