diff --git a/core/modules/system/system.install b/core/modules/system/system.install
index e178297..31b8344 100644
--- a/core/modules/system/system.install
+++ b/core/modules/system/system.install
@@ -672,7 +672,7 @@ function system_requirements($phase) {
         }
       }
 
-      $description = t('Set xdebug_.max_nesting_level=@level in your PHP configuration as some pages in your Drupal site will not work when this setting is too low.', array('@level' => $minimum_nesting_level));
+      $description = t('Set xdebug.max_nesting_level=@level in your PHP configuration as some pages in your Drupal site will not work when this setting is too low.', array('@level' => $minimum_nesting_level));
       if ($ini_location !== FALSE) {
         $description .= ' ' . t('Your Xdebug configuration can be modified in @ini_location.', array('@ini_location' => $ini_location));
       }