diff --git a/calendar/delete.php b/calendar/delete.php
index 8a3d0977036..7ab989a471f 100644
--- a/calendar/delete.php
+++ b/calendar/delete.php
@@ -68,8 +68,8 @@ $event->count_repeats();
 
 // Is used several times, and sometimes with modification if required
 $viewcalendarurl = new moodle_url(CALENDAR_URL.'view.php', array('view'=>'upcoming'));
-$viewcalendarurl->param('cal_y', date('Y', $event->timestart));
-$viewcalendarurl->param('cal_m', date('m', $event->timestart));
+$viewcalendarurl->param('cal_y', userdate($event->timestart, '%Y'));
+$viewcalendarurl->param('cal_m', userdate($event->timestart, '%m'));
 
 // If confirm is set (PARAM_BOOL) then we have confirmation of initention to delete
 if ($confirm) {
@@ -124,4 +124,4 @@ $event->time = calendar_format_event_time($event, time(), null, false);
 calendar_print_event($event, false);
 
 echo $OUTPUT->box_end();
-echo $OUTPUT->footer();
\ No newline at end of file
+echo $OUTPUT->footer();
diff --git a/calendar/event.php b/calendar/event.php
index dd98be36dec..130e682351f 100644
--- a/calendar/event.php
+++ b/calendar/event.php
@@ -168,9 +168,9 @@ if ($data) {
 
     $params = array(
         'view' => 'day',
-        'cal_d' => date('j', $event->timestart),
-        'cal_m' => date('n', $event->timestart),
-        'cal_y' => date('y', $event->timestart),
+        'cal_d' => userdate($event->timestart, '%d'),
+        'cal_m' => userdate($event->timestart, '%m'),
+        'cal_y' => userdate($event->timestart, '%Y'),
     );
     $eventurl = new moodle_url('/calendar/view.php', $params);
     if (!empty($event->courseid) && $event->courseid != SITEID) {