From 85017681d0147475dfe7e4f6b2130be4bcdf4445 Mon Sep 17 00:00:00 2001
From: Andrew McMillan <andrew@morphoss.com>
Date: Mon, 19 Mar 2012 12:33:45 +1300
Subject: [PATCH] More comprehensive fix for collections where sync_token does
 not compute.

---
 inc/DAVResource.php | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/inc/DAVResource.php b/inc/DAVResource.php
index a5c9a90d..246d6521 100644
--- a/inc/DAVResource.php
+++ b/inc/DAVResource.php
@@ -1632,8 +1632,10 @@ EOQRY;
         break;
 
       case 'DAV::sync-token':
-        if ( ! $this->_is_collection || $this->_is_principal ) return false;
-        $reply->NSElement($prop, $tag, $this->sync_token() );
+        if ( ! $this->_is_collection ) return false;
+        $sync_token = $this->sync_token();
+        if ( empty($sync_token) ) return false;
+        $reply->NSElement($prop, $tag, $sync_token );
         break;
 
       case 'http://calendarserver.org/ns/:calendar-proxy-read-for':