diff --git a/library/Icinga/Application/ApplicationBootstrap.php b/library/Icinga/Application/ApplicationBootstrap.php
index 342ffd88d..df8d6a0e1 100644
--- a/library/Icinga/Application/ApplicationBootstrap.php
+++ b/library/Icinga/Application/ApplicationBootstrap.php
@@ -456,13 +456,8 @@ abstract class ApplicationBootstrap
     protected function setupTimezone()
     {
         $timeZoneString = $this->config->global !== null ? $this->config->global->get('timezone', 'UTC') : 'UTC';
-        try {
-            $tz = new DateTimeZone($timeZoneString);
-        } catch (Exception $e) {
-            throw new ConfigurationError(t('Invalid timezone') . ' "' . $timeZoneString . '"');
-        }
         date_default_timezone_set($timeZoneString);
-        DateTimeFactory::setConfig(array('timezone' => $tz));
+        DateTimeFactory::setConfig(array('timezone' => $timeZoneString));
         return $this;
     }
 
diff --git a/library/Icinga/Application/Web.php b/library/Icinga/Application/Web.php
index 9b6c6463b..6ce858d10 100644
--- a/library/Icinga/Application/Web.php
+++ b/library/Icinga/Application/Web.php
@@ -337,13 +337,12 @@ class Web extends ApplicationBootstrap
         }
 
         try {
-            $tz = new DateTimeZone($userTimezone);
-        } catch (Exception $e) {
+            DateTimeFactory::setConfig(array('timezone' => $userTimezone));
+            date_default_timezone_set($userTimezone);
+        } catch (ConfigurationError $e) {
             return parent::setupTimezone();
         }
 
-        date_default_timezone_set($userTimezone);
-        DateTimeFactory::setConfig(array('timezone' => $tz));
         return $this;
     }
 
diff --git a/library/Icinga/Test/BaseTestCase.php b/library/Icinga/Test/BaseTestCase.php
index 847559739..e426dce9c 100644
--- a/library/Icinga/Test/BaseTestCase.php
+++ b/library/Icinga/Test/BaseTestCase.php
@@ -22,7 +22,6 @@ namespace {
 namespace Icinga\Test {
 
     use \Exception;
-    use \DateTimeZone;
     use \RuntimeException;
     use \Mockery;
     use \Zend_Config;
@@ -113,7 +112,7 @@ namespace Icinga\Test {
         public static function setupTimezone()
         {
             date_default_timezone_set('UTC');
-            DateTimeFactory::setConfig(array('timezone' => new DateTimeZone('UTC')));
+            DateTimeFactory::setConfig(array('timezone' => 'UTC'));
         }
 
         /**
diff --git a/library/Icinga/Util/DateTimeFactory.php b/library/Icinga/Util/DateTimeFactory.php
index 9dd854aa7..413af958c 100644
--- a/library/Icinga/Util/DateTimeFactory.php
+++ b/library/Icinga/Util/DateTimeFactory.php
@@ -29,8 +29,9 @@
 
 namespace Icinga\Util;
 
-use \DateTime;
-use \DateTimeZone;
+use Exception;
+use DateTime;
+use DateTimeZone;
 use Icinga\Util\ConfigAwareFactory;
 use Icinga\Exception\ConfigurationError;
 
@@ -55,10 +56,13 @@ class DateTimeFactory implements ConfigAwareFactory
      */
     public static function setConfig($config)
     {
-        if (!array_key_exists('timezone', $config)) {
-            throw new ConfigurationError(t('"DateTimeFactory" expects a valid time zone to be set via "setConfig"'));
+        try {
+            $tz = new DateTimeZone(isset($config['timezone']) ? $config['timezone'] : '');
+        } catch (Exception $e) {
+            throw new ConfigurationError('"DateTimeFactory" expects a valid time zone be set via "setConfig"');
         }
-        self::$timeZone = $config['timezone'];
+
+        self::$timeZone = $tz;
     }
 
     /**
diff --git a/test/php/application/views/helpers/DateFormatTest.php b/test/php/application/views/helpers/DateFormatTest.php
index 04e5e6a90..8de8442f6 100644
--- a/test/php/application/views/helpers/DateFormatTest.php
+++ b/test/php/application/views/helpers/DateFormatTest.php
@@ -5,7 +5,6 @@
 namespace Tests\Icinga\Views\Helper;
 
 use Mockery;
-use DateTimeZone;
 use Zend_View_Helper_DateFormat;
 use Icinga\Test\BaseTestCase;
 use Icinga\Application\Config;
@@ -26,12 +25,12 @@ class DateFormatTest extends BaseTestCase
     {
         parent::tearDown();
         Config::$configDir = $this->oldConfigDir;
-        DateTimeFactory::setConfig(array('timezone' => new DateTimeZone(date_default_timezone_get())));
+        DateTimeFactory::setConfig(array('timezone' => date_default_timezone_get()));
     }
 
     public function testFormatReturnsCorrectDateWithTimezoneApplied()
     {
-        DateTimeFactory::setConfig(array('timezone' => new DateTimeZone('Europe/Berlin')));
+        DateTimeFactory::setConfig(array('timezone' => 'Europe/Berlin'));
         $helper = new Zend_View_Helper_DateFormat($this->getRequestMock());
 
         $this->assertEquals(