From a9c6082e4f36fe91e2ea5ee6f8a662d359ceff92 Mon Sep 17 00:00:00 2001
From: Markus Unterwaditzer <markus@unterwaditzer.net>
Date: Wed, 5 Mar 2014 18:36:07 +0100
Subject: [PATCH] Fix bug

http://bugs.python.org/issue13936
---
 vdirsyncer/storage/dav/caldav.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/vdirsyncer/storage/dav/caldav.py b/vdirsyncer/storage/dav/caldav.py
index 482900e..1560b89 100644
--- a/vdirsyncer/storage/dav/caldav.py
+++ b/vdirsyncer/storage/dav/caldav.py
@@ -72,7 +72,7 @@ class CaldavStorage(DavStorage):
             </C:calendar-query>'''
         start = self.start_date
         end = self.end_date
-        if start and end:
+        if start is not None and end is not None:
             start = start.strftime(CALDAV_DT_FORMAT)
             end = end.strftime(CALDAV_DT_FORMAT)
             caldavfilter = ('<C:time-range start="{start}" end="{end}"/>'