ZP-198 #comment Warnings on recurrence class #time 15m

git-svn-id: https://z-push.org/svn/z-push/trunk@1458 b7dd7b3b-3a3c-0410-9da9-bee62a6cc5b5

src/backend/zarafa/mapi/class.recurrence.php

@@ -1158,7 +1158,7 @@
                 foreach($recipientRows as $key => $recipient) {
                     $found = false;
                     foreach($exception_recips as $excep_recip) {
-                        if ($recipient[PR_SEARCH_KEY] == $excep_recip[PR_SEARCH_KEY])
+                        if (isset($recipient[PR_SEARCH_KEY]) && isset($excep_recip[PR_SEARCH_KEY]) && $recipient[PR_SEARCH_KEY] == $excep_recip[PR_SEARCH_KEY])
                             $found = true;
                     }