diff --git a/libisoburn/trunk/xorriso/xorriso.1 b/libisoburn/trunk/xorriso/xorriso.1
index 1eac0e93..7a9a3b0d 100644
--- a/libisoburn/trunk/xorriso/xorriso.1
+++ b/libisoburn/trunk/xorriso/xorriso.1
@@ -3485,9 +3485,10 @@ the local filesystem, insert these options immediately before -commit :
 .br
  -find / -type f -pending_data -exec set_filter --zisofs -- \\
 .br
-Option -disk_dev_ino depends on stable device and inode numbers on disk.
-Without it, an update run will probably save no time but last longer than
-a full backup. Such a slow run might produce a smaller backup, though.
+Options -disk_dev_ino and -for_backup depend on stable device and inode numbers
+on disk. Without them, an update run may use -md5 "on" to match recorded MD5
+sums against the current file content on hard disk. This is usually much faster
+than the default which compares both contents directly.
 .br 
 With \fBmount\fR option \fB-o "sbsector="\fR on Linux resp. \fB-s\fR on FreeBSD
 it is possible to access the session trees which represent the older backup
diff --git a/libisoburn/trunk/xorriso/xorriso_timestamp.h b/libisoburn/trunk/xorriso/xorriso_timestamp.h
index 37cc5ee7..35f7d601 100644
--- a/libisoburn/trunk/xorriso/xorriso_timestamp.h
+++ b/libisoburn/trunk/xorriso/xorriso_timestamp.h
@@ -1 +1 @@
-#define Xorriso_timestamP "2009.08.25.191217"
+#define Xorriso_timestamP "2009.08.25.191325"