Mentioned missing mkisofs -old-root functionality in man page

libisoburn/trunk/xorriso/xorriso.texi

@@ -44,7 +44,7 @@
 @c man .\" First parameter, NAME, should be all caps
 @c man .\" Second parameter, SECTION, should be 1-8, maybe w/ subsection
 @c man .\" other parameters are allowed: see man(7), man(1)
-@c man .TH XORRISO 1 "Jan 06, 2011"
+@c man .TH XORRISO 1 "Jan 19, 2011"
 @c man .\" Please adjust this date whenever revising the manpage.
 @c man .\"
 @c man .\" Some roff macros, for reference:
@@ -4172,6 +4172,9 @@ directory is added to the image. At the same occasion directory names get
 allowed to violate the standard by -compliance option allow_dir_id_ext.
 This may be avoided by option -disallow_dir_id_ext.
 @*
+Currently there is no emulation for -root and -old-root. Incremental backups
+can be done by native xorriso command -update_r. See also EXAMPLES section.
+@*
 Not original mkisofs options are @minus{}@minus{}quoted_path_list ,
 @minus{}@minus{}hardlinks , @minus{}@minus{}acl ,
 @minus{}@minus{}xattr , @minus{}@minus{}md5 , @minus{}@minus{}stdio_sync .
@@ -5151,6 +5154,9 @@ get endangered by the new write operation, while the newest backup is
 stored safely on a different media.
 Always have a blank media ready to perform a full backup in case the update
 attempt fails due to insufficient remaining capacity.
+@*
+@sp 1
+This example produces a result similar to  -root / -old-root / with mkisofs.
 @c man .SS
 @c man .B Restore directory trees from a particular ISO session to disk
 @node ExRestore, ExRecovery, ExIncBackup, Examples
@@ -5316,7 +5322,7 @@ Thomas Schmitt <scdbackup@@gmx.net>
 for libburnia-project.org
 @c man .SH COPYRIGHT
 @section Copyright
-Copyright (c) 2007 - 2010 Thomas Schmitt
+Copyright (c) 2007 - 2011 Thomas Schmitt
 @*
 Permission is granted to distribute this text freely. It shall only be
 modified in sync with the technical properties of xorriso. If you make use