diff --git a/calendar/lib.php b/calendar/lib.php
index 39e3a019508..3ddaf75ec73 100644
--- a/calendar/lib.php
+++ b/calendar/lib.php
@@ -469,7 +469,7 @@ function calendar_sql_where($tstart, $tend, $users, $groups, $courses, $withdura
         // Just basic time filtering
         $whereclause = $timeclause;
     }
-    return $whereclause.' AND visible = 1';
+    return $whereclause;
 }
 
 function calendar_top_controls($type, $data) {
@@ -1145,10 +1145,10 @@ function calendar_edit_event_allowed($event) {
     return false;
 }
 
-function calendar_get_default_courses($overridereferer = true) {
+function calendar_get_default_courses($ignoreref = false) {
     global $USER, $CFG, $SESSION;
 
-    if(!empty($SESSION->cal_course_referer) && $overridereferer) {
+    if(!empty($SESSION->cal_course_referer) && !$ignoreref) {
         return array($SESSION->cal_course_referer => 1);
     }
 
diff --git a/calendar/view.php b/calendar/view.php
index db762e7ad52..52e16ef7a1e 100644
--- a/calendar/view.php
+++ b/calendar/view.php
@@ -123,13 +123,25 @@
 
     echo '<td width="100%" valign="top">';
 
-    $conform = ($_GET['view'] == 'month' && $SESSION->cal_show_course === true);
+    if($_GET['view'] == 'month') {
+        if(is_numeric($SESSION->cal_show_course)) {
+            $defaultcourses = array($SESSION->cal_show_course => 1);
+        }
+        else if($SESSION->cal_show_course === true) {
+            $defaultcourses = calendar_get_default_courses(true);
+        }
+        else if($SESSION->cal_show_course === false) {
+            $defaultcourses = array();
+        }
+    }
+    else {
+        $defaultcourses = calendar_get_default_courses();
+    }
 
-    $defaultcourses = calendar_get_default_courses(!$conform);
     $courses = array();
 
     calendar_set_filters($courses, $groups, $users, $defaultcourses, $defaultcourses);
-
+/*
     // Are we left with a bad filter in effect?
     if($_GET['view'] != 'month' && !empty($SESSION->cal_course_referer)) {
         if(is_numeric($SESSION->cal_show_course)) {
@@ -141,7 +153,7 @@
             $SESSION->cal_show_course = intval($SESSION->cal_course_referer);
         }
     }
-
+*/
     switch($_GET['view']) {
         case 'event':
             optional_variable($_GET['id'], 0);