diff --git a/win/rfb_win32/OSVersion.h b/win/rfb_win32/OSVersion.h
new file mode 100644
index 0000000..18ec003
--- /dev/null
+++ b/win/rfb_win32/OSVersion.h
@@ -0,0 +1,53 @@
+/* Copyright (C) 2002-2005 RealVNC Ltd.  All Rights Reserved.
+ * 
+ * This is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ * 
+ * This software is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ * 
+ * You should have received a copy of the GNU General Public License
+ * along with this software; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307,
+ * USA.
+ */
+
+// -=- OSVersion.h
+
+// Operating system version info.
+// GetVersionInfo is called once at process initialisation, and any
+// extra flags (such as isWinNT) are calculated and saved at that
+// point.  It is assumed that the OS Version seldom changes during a
+// program's execution...
+
+#ifndef __RFB_WIN32_OS_VERSION_H__
+#define __RFB_WIN32_OS_VERSION_H__
+
+#include <windows.h>
+
+namespace rfb {
+
+  namespace win32 {
+
+    extern struct OSVersionInfo : OSVERSIONINFO {
+      OSVersionInfo();
+
+      // Is the OS one of the NT family (NT 3.51, NT4.0, 2K, XP, etc.)?
+      bool isPlatformNT;
+      // Is one of the Windows family?
+      bool isPlatformWindows;
+
+      // Is this OS one of those that blue-screens when grabbing another desktop (NT4 pre SP3)?
+      bool cannotSwitchDesktop;
+
+    } osVersion;
+
+  };
+
+};
+
+#endif // __RFB_WIN32_OS_VERSION_H__