diff --git a/typo3/sysext/core/Classes/Configuration/ConfigurationManager.php b/typo3/sysext/core/Classes/Configuration/ConfigurationManager.php
index 071ffa564e9c63802d646eb721b094469d26ca66..4ba9e73e9c2af427cf7632da26c97f0c00ef9b4b 100644
--- a/typo3/sysext/core/Classes/Configuration/ConfigurationManager.php
+++ b/typo3/sysext/core/Classes/Configuration/ConfigurationManager.php
@@ -322,9 +322,7 @@ class ConfigurationManager
             $localConfigurationFile,
             '<?php' . LF .
                 'return ' .
-                    ArrayUtility::arrayExport(
-                        ArrayUtility::renumberKeysToAvoidLeapsIfKeysAreAllNumeric($configuration)
-                    ) .
+                    ArrayUtility::arrayExport($configuration) .
                 ';' . LF,
             true
         );