diff --git a/src/Symfony/Bridge/PhpUnit/DeprecationErrorHandler.php b/src/Symfony/Bridge/PhpUnit/DeprecationErrorHandler.php
index 6a7ad1fa98828..550cbe375f7a1 100644
--- a/src/Symfony/Bridge/PhpUnit/DeprecationErrorHandler.php
+++ b/src/Symfony/Bridge/PhpUnit/DeprecationErrorHandler.php
@@ -112,7 +112,7 @@ public static function register($mode = 0)
             $trace = debug_backtrace(true);
             $group = 'other';
 
-            $isWeak = DeprecationErrorHandler::MODE_WEAK === $mode || (DeprecationErrorHandler::MODE_WEAK_VENDORS === $mode && $isVendor = $inVendors($file));
+            $isWeak = DeprecationErrorHandler::MODE_WEAK === $mode || (self::MODE_WEAK_VENDORS === $mode && $isVendor = $inVendors($file));
 
             $i = count($trace);
             while (1 < $i && (!isset($trace[--$i]['class']) || ('ReflectionMethod' === $trace[$i]['class'] || 0 === strpos($trace[$i]['class'], 'PHPUnit_') || 0 === strpos($trace[$i]['class'], 'PHPUnit\\')))) {
@@ -196,7 +196,7 @@ public static function register($mode = 0)
                     $colorize = function ($str) { return $str; };
                 }
                 if ($currErrorHandler !== $deprecationHandler) {
-                    echo "\n", $colorize('THE ERROR HANDLER HAS CHANGED!', true), "\n";
+                    echo "\n", $colorize("THE ERROR HANDLER HAS CHANGED!\n".var_export(error_get_last(), true), true), "\n";
                 }
 
                 $cmp = function ($a, $b) {
diff --git a/src/Symfony/Bridge/PhpUnit/Tests/DeprecationErrorHandler/failure.phpt b/src/Symfony/Bridge/PhpUnit/Tests/DeprecationErrorHandler/failure.phpt
new file mode 100644
index 0000000000000..2622b33e371e2
--- /dev/null
+++ b/src/Symfony/Bridge/PhpUnit/Tests/DeprecationErrorHandler/failure.phpt
@@ -0,0 +1,43 @@
+--TEST--
+Test DeprecationErrorHandler failure
+--FILE--
+<?php
+namespace Symfony\Bridge\PhpUnit;
+function error_get_last()
+{
+    return array(
+        'type' => E_ERROR,
+        'message' => 'failed to load flux capacitor',
+        'file' => '/wherever/the/deprecation_handler_is',
+        'line' => 42
+    );
+}
+
+putenv('SYMFONY_DEPRECATIONS_HELPER');
+putenv('ANSICON');
+putenv('ConEmuANSI');
+putenv('TERM');
+
+$vendor = __DIR__;
+while (!file_exists($vendor.'/vendor')) {
+    $vendor = dirname($vendor);
+}
+define('PHPUNIT_COMPOSER_INSTALL', $vendor.'/vendor/autoload.php');
+require PHPUNIT_COMPOSER_INSTALL;
+require_once __DIR__.'/../../bootstrap.php';
+
+trigger_error('test failure', E_USER_DEPRECATED);
+set_error_handler('var_dump');
+
+--EXPECTF--
+THE ERROR HANDLER HAS CHANGED!
+array (
+  'type' => 1,
+  'message' => 'failed to load flux capacitor',
+  'file' => '/wherever/the/deprecation_handler_is',
+  'line' => 42,
+)
+
+Other deprecation notices (1)
+
+test failure: 1x