From ee2aa33cbc5f257f637ab78cdd08584fbfde374d Mon Sep 17 00:00:00 2001
From: Kovid Goyal <kovid@kovidgoyal.net>
Date: Fri, 11 May 2012 12:04:54 +0530
Subject: [PATCH] ...

---
 src/calibre/ebooks/mobi/writer8/mobi.py | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/src/calibre/ebooks/mobi/writer8/mobi.py b/src/calibre/ebooks/mobi/writer8/mobi.py
index eabcf97047..48e0833ddb 100644
--- a/src/calibre/ebooks/mobi/writer8/mobi.py
+++ b/src/calibre/ebooks/mobi/writer8/mobi.py
@@ -138,6 +138,8 @@ class MOBIHeader(Header): # {{{
     unknown2 = zeroes(8)
 
     # 192: FDST
+    # In MOBI 6 the fdst record is instead two two byte fields storing the
+    # index of the first and last content records
     fdst_record = DYN
     fdst_count = DYN