diff --git a/calendar/inc/class.calendar_hooks.inc.php b/calendar/inc/class.calendar_hooks.inc.php
index 96a2b1f73c..d7dee047d7 100644
--- a/calendar/inc/class.calendar_hooks.inc.php
+++ b/calendar/inc/class.calendar_hooks.inc.php
@@ -162,7 +162,7 @@ class calendar_hooks
 			'Saturday' => lang('Saturday')
 		);
 		$birthdays_as_events = array(
-			'0'        => lang('None'),
+			'none'     => lang('None'),
 			'birthday' => lang('Birthdays'),
 			'holiday'  => lang('Holidays')
 		);
@@ -325,7 +325,7 @@ class calendar_hooks
 				'label'  => 'Show birthdays as events',
 				'name'   => 'birthdays_as_events',
 				'help'   => 'Show birthdays as all day non-blocking events as well as via mouseover of the date.',
-				'default'=> '0'
+				'default'=> 'none'
 			),
 			'limit_all_day_lines' => array(
 				'type'   => 'input',
diff --git a/calendar/setup/tables_update.inc.php b/calendar/setup/tables_update.inc.php
index bafffd7981..1c2ea14068 100644
--- a/calendar/setup/tables_update.inc.php
+++ b/calendar/setup/tables_update.inc.php
@@ -2759,7 +2759,7 @@ function calendar_upgrade17_1()
 {
 	// Update birthdays as events preference from boolean
 	$change = function($attr, $old_value, $owner) {
-		return $old_value ? 'birthday' : '0';
+		return $old_value ? 'birthday' : 'none';
 	};
 	Api\Preferences::change_preference('calendar', 'birthdays_as_events', $change);
 	return $GLOBALS['setup_info']['calendar']['currentver'] = '17.1.001';