From 9571e23b19b2deffcb1be9848bb2365429bd4878 Mon Sep 17 00:00:00 2001
From: Charles Haley <>
Date: Wed, 6 Oct 2010 16:07:08 +0100
Subject: [PATCH] Better fix for #7078

---
 src/calibre/ebooks/metadata/book/base.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/calibre/ebooks/metadata/book/base.py b/src/calibre/ebooks/metadata/book/base.py
index 45f69508c1..551d8ebe44 100644
--- a/src/calibre/ebooks/metadata/book/base.py
+++ b/src/calibre/ebooks/metadata/book/base.py
@@ -516,7 +516,7 @@ class Metadata(object):
             if datatype == 'text' and cmeta['is_multiple']:
                 res = u', '.join(res)
             elif datatype == 'series' and series_with_index:
-                if self.get_extra(key):
+                if self.get_extra(key) is not None:
                     res = res + \
                         ' [%s]'%self.format_series_index(val=self.get_extra(key))
             elif datatype == 'datetime':