diff --git a/calendar/view.php b/calendar/view.php
index 9fa5bdd..224db4c 100644
--- a/calendar/view.php
+++ b/calendar/view.php
@@ -156,7 +156,7 @@
             calendar_show_day($day, $mon, $yr, $courses, $groups, $users, $courseid);
         break;
         case 'month':
-            calendar_show_month_detailed($mon, $yr, $courses, $groups, $users, $courseid);
+            calendar_show_month_detailed($day, $mon, $yr, $courses, $groups, $users, $courseid);
         break;
         case 'upcoming':
             calendar_show_upcoming_events($courses, $groups, $users, get_user_preferences('calendar_lookahead', CALENDAR_UPCOMING_DAYS), get_user_preferences('calendar_maxevents', CALENDAR_UPCOMING_MAXEVENTS), $courseid);
@@ -306,11 +306,10 @@ function calendar_show_day($d, $m, $y, $courses, $groups, $users, $courseid) {
     }
 }
 
-function calendar_show_month_detailed($m, $y, $courses, $groups, $users, $courseid) {
+function calendar_show_month_detailed($d, $m, $y, $courses, $groups, $users, $courseid) {
     global $CFG, $SESSION, $USER, $CALENDARDAYS;
-    global $day, $mon, $yr;
 
-    $getvars = 'from=month&cal_d='.$day.'&cal_m='.$mon.'&cal_y='.$yr; // For filtering
+    $getvars = 'from=month&cal_d='.$d.'&cal_m='.$m.'&cal_y='.$y; // For filtering
 
     $display = &New stdClass;
     $display->minwday = get_user_preferences('calendar_startwday', CALENDAR_STARTING_WEEKDAY);