From 5114792fce145e757d2a85f17ce4b0ee5fda951e Mon Sep 17 00:00:00 2001
From: Kovid Goyal <kovid@kovidgoyal.net>
Date: Fri, 9 Apr 2010 10:10:54 +0530
Subject: [PATCH] Fix #5234 (Crash during EPUB to MOBI conversion (Kindle 2))

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

diff --git a/src/calibre/ebooks/oeb/reader.py b/src/calibre/ebooks/oeb/reader.py
index e829891a45..ebe6e78d08 100644
--- a/src/calibre/ebooks/oeb/reader.py
+++ b/src/calibre/ebooks/oeb/reader.py
@@ -470,6 +470,8 @@ class OEBReader(object):
         if item is None:
             return False
         ncx = item.data
+        if ncx is None:
+            return False
         ptargets = xpath(ncx, 'ncx:pageList/ncx:pageTarget')
         if not ptargets:
             return False