diff --git a/uisimulator/x11/kernel.h b/uisimulator/x11/kernel.h
new file mode 100644
index 0000000000..32c7d9beb9
--- /dev/null
+++ b/uisimulator/x11/kernel.h
@@ -0,0 +1,24 @@
+/***************************************************************************
+ *             __________               __   ___.                  
+ *   Open      \______   \ ____   ____ |  | _\_ |__   _______  ___  
+ *   Source     |       _//  _ \_/ ___\|  |/ /| __ \ /  _ \  \/  /  
+ *   Jukebox    |    |   (  <_> )  \___|    < | \_\ (  <_> > <  <   
+ *   Firmware   |____|_  /\____/ \___  >__|_ \|___  /\____/__/\_ \  
+ *                     \/            \/     \/    \/            \/ 
+ * $Id$
+ *
+ * Copyright (C) 2002 by Daniel Stenberg <daniel@haxx.se>
+ *
+ * All files in this archive are subject to the GNU General Public License.
+ * See the file COPYING in the source tree root for full license agreement.
+ *
+ * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
+ * KIND, either express or implied.
+ *
+ ****************************************************************************/
+
+#include "../../firmware/kernel.h"
+
+#define sleep(x) x11_sleep(x)
+
+void x11_sleep(int);