diff --git a/Source/Examples/Tests/S04_Input_Logger.cs b/Source/Examples/Tests/S04_Input_Logger.cs
index d5b203bc..6290352f 100644
--- a/Source/Examples/Tests/S04_Input_Logger.cs
+++ b/Source/Examples/Tests/S04_Input_Logger.cs
@@ -24,7 +24,6 @@ namespace Examples.Tests
     {
         InputDriver driver;
         Dictionary<IntPtr, ListBox> keyboardListBoxes = new Dictionary<IntPtr, ListBox>(4);
-        bool stop_polling;
 
         public S04_Input_Logger()
         {
diff --git a/Source/Examples/Tutorial/T01_Simple_Window.cs b/Source/Examples/Tutorial/T01_Simple_Window.cs
index 762296c8..a06990c0 100644
--- a/Source/Examples/Tutorial/T01_Simple_Window.cs
+++ b/Source/Examples/Tutorial/T01_Simple_Window.cs
@@ -22,10 +22,27 @@ namespace Examples.Tutorial
             this.CreateWindow(new DisplayMode(800, 600));
         }
 
+        /// <summary>
+        /// Override the OnResize method to respond to window resize events.
+        /// Do not forget to call base.OnResize() so that event listeners
+        /// will be notified of window resize events!
+        /// </summary>
+        /// <param name="e"></param>
+        protected override void OnResize(OpenTK.Platform.ResizeEventArgs e)
+        {
+            GL.Viewport(0, 0, e.Width, e.Height);
+
+            GL.MatrixMode(GL.Enums.MatrixMode.PROJECTION);
+            GL.LoadIdentity();
+            GL.Ortho(-1.0, 1.0, -1.0, 1.0, 0.0, 4.0);
+
+            base.OnResize(e);
+        }
+
         /// <summary>
         /// Override the OnRenderFrame method to add your drawing code.
         /// Do not forget to call base.OnRenderFrame() so that event listeners
-        /// will be notified every time a frame is drawn!
+        /// will be notified of frame rendering events!
         /// </summary>
         /// <param name="e">Not used.</param>
         public override void OnRenderFrame(EventArgs e)
diff --git a/Source/OpenTK/OpenGL/GLHelper.cs b/Source/OpenTK/OpenGL/GLHelper.cs
index 9d133ca1..71da4bfe 100644
--- a/Source/OpenTK/OpenGL/GLHelper.cs
+++ b/Source/OpenTK/OpenGL/GLHelper.cs
@@ -360,31 +360,46 @@ namespace OpenTK.OpenGL
 
         internal class GetProcAddressWindows : IGetProcAddress
         {
+            [System.Runtime.InteropServices.DllImport(Library, EntryPoint = "wglGetProcAddress", ExactSpelling = true)]
+            private static extern IntPtr wglGetProcAddress(String lpszProc);
+
             public IntPtr GetProcAddress(string function)
             {
-                return OpenTK.Platform.Windows.Wgl.Imports.GetProcAddress(function);
+                return wglGetProcAddress(function);
             }
         }
 
         internal class GetProcAddressX11 : IGetProcAddress
         {
+            [DllImport(Library, EntryPoint = "glXGetProcAddress")]
+            private static extern IntPtr glxGetProcAddress([MarshalAs(UnmanagedType.LPTStr)] string procName);
+
             public IntPtr GetProcAddress(string function)
             {
-                return X11.Glx.GetProcAddress(function);
+                return glxGetProcAddress(function);
             }
         }
 
         internal class GetProcAddressOSX : IGetProcAddress
         {
+            private const string Library = "libdl.dylib";
+
+            [DllImport(Library, EntryPoint = "NSIsSymbolNameDefined")]
+            private static extern bool NSIsSymbolNameDefined(string s);
+            [DllImport(Library, EntryPoint = "NSLookupAndBindSymbol")]
+            private static extern IntPtr NSLookupAndBindSymbol(string s);
+            [DllImport(Library, EntryPoint = "NSAddressOfSymbol")]
+            private static extern IntPtr NSAddressOfSymbol(IntPtr symbol);
+
             public IntPtr GetProcAddress(string function)
             {
                 string fname = "_" + function;
-                if (!OSX.Functions.NSIsSymbolNameDefined(fname))
+                if (!NSIsSymbolNameDefined(fname))
                     return IntPtr.Zero;
 
-                IntPtr symbol = OSX.Functions.NSLookupAndBindSymbol(fname);
+                IntPtr symbol = NSLookupAndBindSymbol(fname);
                 if (symbol != IntPtr.Zero)
-                    symbol = OSX.Functions.NSAddressOfSymbol(symbol);
+                    symbol = NSAddressOfSymbol(symbol);
 
                 return symbol;
             }
@@ -439,7 +454,7 @@ namespace OpenTK.OpenGL
 
         #endregion
 
-        #region private static Delegate GetExtensionDelegate(string name, Type signature)
+        #region internal static Delegate GetExtensionDelegate(string name, Type signature)
 
         /// <summary>
         /// Creates a System.Delegate that can be used to call a dynamically exported OpenGL function.
@@ -450,7 +465,7 @@ namespace OpenTK.OpenGL
         /// A System.Delegate that can be used to call this OpenGL function or null
         /// if the function is not available in the current OpenGL context.
         /// </returns>
-        private static Delegate GetExtensionDelegate(string name, Type signature)
+        internal static Delegate GetExtensionDelegate(string name, Type signature)
         {
             IntPtr address = GetAddress(name);
 
diff --git a/Source/OpenTK/OpenGL/GluHelper.cs b/Source/OpenTK/OpenGL/GluHelper.cs
index 16f99bba..b01dadef 100644
--- a/Source/OpenTK/OpenGL/GluHelper.cs
+++ b/Source/OpenTK/OpenGL/GluHelper.cs
@@ -47,7 +47,7 @@ namespace OpenTK.OpenGL
         {
             MethodInfo m = importsClass.GetMethod(name.Substring(3), BindingFlags.Static | BindingFlags.NonPublic);
             return 
-                Utilities.GetExtensionDelegate(name, signature) ??
+                GL.GetExtensionDelegate(name, signature) ??
                 (m != null ? Delegate.CreateDelegate(signature, m) : null);
         }
 
diff --git a/Source/OpenTK/Platform/Windows/WglHelper.cs b/Source/OpenTK/Platform/Windows/WglHelper.cs
index 7060629c..eed612e4 100644
--- a/Source/OpenTK/Platform/Windows/WglHelper.cs
+++ b/Source/OpenTK/Platform/Windows/WglHelper.cs
@@ -62,12 +62,12 @@ namespace OpenTK.Platform.Windows
             if (importsClass.GetMethod(realName,
                 BindingFlags.NonPublic | BindingFlags.Static) != null)
             {
-                d = Utilities.GetExtensionDelegate(name, signature) ??
+                d = GetExtensionDelegate(name, signature) ??
                     Delegate.CreateDelegate(signature, typeof(Imports), realName);
             }
             else
             {
-                d = Utilities.GetExtensionDelegate(name, signature);
+                d = GetExtensionDelegate(name, signature);
             }
 
             return d;
@@ -75,6 +75,35 @@ namespace OpenTK.Platform.Windows
 
         #endregion
 
+        #region private static Delegate GetExtensionDelegate(string name, Type signature)
+
+        /// <summary>
+        /// Creates a System.Delegate that can be used to call a dynamically exported OpenGL function.
+        /// </summary>
+        /// <param name="name">The name of the OpenGL function (eg. "glNewList")</param>
+        /// <param name="signature">The signature of the OpenGL function.</param>
+        /// <returns>
+        /// A System.Delegate that can be used to call this OpenGL function or null
+        /// if the function is not available in the current OpenGL context.
+        /// </returns>
+        private static Delegate GetExtensionDelegate(string name, Type signature)
+        {
+            IntPtr address = Imports.GetProcAddress(name);
+
+            if (address == IntPtr.Zero ||
+                address == new IntPtr(1) ||     // Workaround for buggy nvidia drivers which return
+                address == new IntPtr(2))       // 1 or 2 instead of IntPtr.Zero for some extensions.
+            {
+                return null;
+            }
+            else
+            {
+                return Marshal.GetDelegateForFunctionPointer(address, signature);
+            }
+        }
+
+        #endregion
+
         /// <summary>
         /// Loads all Wgl entry points, core and extensions.
         /// </summary>