diff --git a/library/Icinga/Authentication/Manager.php b/library/Icinga/Authentication/Manager.php
index f46153fd7..a818c6081 100644
--- a/library/Icinga/Authentication/Manager.php
+++ b/library/Icinga/Authentication/Manager.php
@@ -404,13 +404,13 @@ class Manager
         $this->fromRemoteUser = true;
         $this->authenticateFromSession();
         if ($this->user !== null) {
-            if ($this->user->getUsername() !== $_SERVER["REMOTE_USER"]) {
+            if (array_key_exists('REMOTE_USER', $_SERVER) && $this->user->getUsername() !== $_SERVER["REMOTE_USER"]) {
                 // Remote user has changed, clear all sessions
                 $this->removeAuthorization();
             }
             return;
         }
-        if ($_SERVER["REMOTE_USER"] !== null) {
+        if (array_key_exists('REMOTE_USER', $_SERVER) && $_SERVER["REMOTE_USER"]) {
             $this->user = new User($_SERVER["REMOTE_USER"]);
             $this->persistCurrentUser();
         }
diff --git a/library/Icinga/Web/Widget/Chart/PieChart.php b/library/Icinga/Web/Widget/Chart/PieChart.php
index 0e4547135..edc4e78fe 100644
--- a/library/Icinga/Web/Widget/Chart/PieChart.php
+++ b/library/Icinga/Web/Widget/Chart/PieChart.php
@@ -43,7 +43,7 @@ class PieChart implements Widget
      */
     private $template =<<<'EOD'
 
-    <div data-icinga-component="app/piechart">
+    <div>
         <img class='inlinepie' src="{url}" width={width} height={height}> </img>
     </div>
 EOD;