diff --git a/libisoburn/libisoburn.h b/libisoburn/libisoburn.h
index a4844a7d..124e4ba8 100644
--- a/libisoburn/libisoburn.h
+++ b/libisoburn/libisoburn.h
@@ -1,10 +1,10 @@
 
 /*
-  API definition of libisoburn.
+  Lower level API definition of libisoburn.
 
   Copyright 2007-2010 Vreixo Formoso Lopes <metalpain2002@yahoo.es>
                   and Thomas Schmitt <scdbackup@gmx.net>
-   Provided under GPL version 2 or later.
+  Provided under GPL version 2 or later.
 */
 
 /**                           Overview
@@ -18,6 +18,9 @@ The price for that is thorough specialization on data files in ISO-9660
 filesystem images. So libisoburn is not suitable for audio (CD-DA) or any
 other CD layout which does not entirely consist of ISO-9660 sessions.
 
+Note that there is a higher level of API: xorriso.h. One should not mix it
+with the API calls of libisoburn.h, libisofs.h, and libburn.h.
+
 
                           Connector functions
 
diff --git a/xorriso/xorriso_timestamp.h b/xorriso/xorriso_timestamp.h
index eb2a5950..dbb8b04c 100644
--- a/xorriso/xorriso_timestamp.h
+++ b/xorriso/xorriso_timestamp.h
@@ -1 +1 @@
-#define Xorriso_timestamP "2010.05.19.160540"
+#define Xorriso_timestamP "2010.05.21.132937"