diff --git a/cpu/i386/serial.c b/cpu/i386/serial.c
index 8b5f8fa..e7025a3 100644
--- a/cpu/i386/serial.c
+++ b/cpu/i386/serial.c
@@ -26,6 +26,9 @@
 /*------------------------------------------------------------------------------+ */
 
 /*
+ * This source code is dual-licensed.  You may use it under the terms of the
+ * GNU General Public License version 2, or under the license below.
+ *
  * This source code has been made available to you by IBM on an AS-IS
  * basis.  Anyone receiving this source is licensed under IBM
  * copyrights to use it in any way he or she deems fit, including