diff --git a/calendar/lib.php b/calendar/lib.php
index 6a67dea3851..975da295d5b 100644
--- a/calendar/lib.php
+++ b/calendar/lib.php
@@ -654,7 +654,7 @@ function calendar_filter_controls($type, $vars = NULL, $course = NULL) {
             $getvars = '&from='.$type;
         break;
         case 'course':
-            if (isset_param('id')) {
+            if ($id > 0) {
                 $getvars = '&from=course&id='.$id;
             } else {
                 $getvars = '&from=course';
diff --git a/mod/forum/view.php b/mod/forum/view.php
index 94afe312a97..ff2018e9689 100644
--- a/mod/forum/view.php
+++ b/mod/forum/view.php
@@ -8,7 +8,7 @@
     $f       = optional_param('f', 0, PARAM_INT);         // Forum ID
     $mode    = optional_param('mode', 0, PARAM_INT);      // Display mode (for single forum)
     $showall = optional_param('showall', '', PARAM_INT);  // show all discussions on one page
-    $group   = optional_param('group', -1, PARAM_INT);    // choose the current group
+    $changegroup = optional_param('group', -1, PARAM_INT);    // choose the current group
     $page    = optional_param('page', 0, PARAM_INT);      // which page to show
     $search  = optional_param('search', '');              // search string
 
@@ -83,8 +83,6 @@
 /// Check to see if groups are being used in this forum
 /// and if so, set $currentgroup to reflect the current group
 
-    $changegroup = isset_param('group') ? $group : -1;  // Group change requested?
-
     if ($forum->type == "teacher") {
         $groupmode = NOGROUPS;
     } else {