Index: System.Windows.Forms/Application.cs
===================================================================
--- System.Windows.Forms/Application.cs (revision 55057)
+++ System.Windows.Forms/Application.cs (working copy)
@@ -300,6 +300,14 @@
                }
 
                public static void Run() {
+                       if (Environment.GetEnvironmentVariable ("MONO_MWF_USE_QUARTZ_BACKEND") != null) {
+                               System.Windows.Forms.OSX.Application.Run ();
+                       } else {
+                               RealRun ();
+                       }
+               }
+
+               internal static void RealRun() {
                        MSG     msg = new MSG();
                        Form    form = null;