diff --git a/common/rfb/UserMsgBox.h b/common/rfb/UserMsgBox.h
new file mode 100644
index 0000000..8b29587
--- /dev/null
+++ b/common/rfb/UserMsgBox.h
@@ -0,0 +1,40 @@
+/* Copyright (C) 2002-2005 RealVNC Ltd.  All Rights Reserved.
+ * Copyright (C) 2010 TigerVNC Team
+ *
+ * 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.
+ */
+#ifndef __RFB_USERMSGBOX_H__
+#define __RFB_USERMSGBOX_H__
+
+namespace rfb {
+  class UserMsgBox {
+  public:
+    enum MsgBoxFlags{
+      M_OK = 0,
+      M_OKCANCEL = 1,
+      M_YESNO = 4,
+      M_ICONERROR = 0x10,
+      M_ICONQUESTION = 0x20,
+      M_ICONWARNING = 0x30,
+      M_ICONINFORMATION = 0x40,
+      M_DEFBUTTON1 = 0,
+      M_DEFBUTTON2 = 0x100
+    };
+    virtual bool showMsgBox(int flags,const char* title, const char* text)=0;
+  };
+}
+
+#endif