diff --git a/typo3/sysext/core/Classes/Autoloader.php b/typo3/sysext/core/Classes/Autoloader.php
index 70f198012d30750152b91fbfe47260fb4bb48060..9d2c84281cf86faa656adaa65da66922d5fd632d 100644
--- a/typo3/sysext/core/Classes/Autoloader.php
+++ b/typo3/sysext/core/Classes/Autoloader.php
@@ -273,34 +273,15 @@ class Autoloader {
 	 * @return void
 	 */
 	static protected function attemptToLoadRegistryWithNamingConventionForGivenClassName($className) {
-		$delimiter = '_';
-		$tempClassName = $className;
-		// To handle namespaced class names, get rid of the first backslash
-		// and replace the remaining ones with underscore. This will simulate
-		// a 'usual' "extbase" structure like 'Tx_ExtensionName_Foo_bar'
-		if (strpos($className, '\\') !== FALSE) {
-			$tempClassName = ltrim($className, '\\');
-			$delimiter = '\\';
-		}
-		$classNameParts = explode($delimiter, $tempClassName, 4);
-		if ((isset($classNameParts[0]) && $classNameParts[0] === 'TYPO3') && (isset($classNameParts[1]) && $classNameParts[1] === 'CMS')) {
-			$extensionKey = \TYPO3\CMS\Core\Utility\GeneralUtility::camelCaseToLowerCaseUnderscored($classNameParts[2]);
-			$classNameWithoutVendorAndProduct = $classNameParts[3];
-		} else {
-			$extensionKey = \TYPO3\CMS\Core\Utility\GeneralUtility::camelCaseToLowerCaseUnderscored($classNameParts[1]);
-			$classNameWithoutVendorAndProduct = $classNameParts[2];
-
-			if (isset($classNameParts[3])) {
-				$classNameWithoutVendorAndProduct .= $delimiter . $classNameParts[3];
-			}
-		}
-
+		$extensionKey = \TYPO3\CMS\Core\Extension\ExtensionManager::getExtensionKeyFromClassName($className);
 		if ($extensionKey) {
 			try {
 				// This will throw a BadFunctionCallException if the extension is not loaded
 				$extensionPath = \TYPO3\CMS\Core\Extension\ExtensionManager::extPath($extensionKey);
-				$classPath = (substr(strtolower($classNameWithoutVendorAndProduct), 0, 5) === 'tests') ? '' : 'Classes/';
-				$classFilePathAndName = $extensionPath . $classPath . strtr($classNameWithoutVendorAndProduct, $delimiter, '/') . '.php';
+				$classNameWithoutVendorAndProduct = \TYPO3\CMS\Core\Extension\ExtensionManager::getClassNameWithoutVendorAndProduct($className);
+				$classesRootPath = (substr(strtolower($classNameWithoutVendorAndProduct), 0, 5) === 'tests') ? '' : 'Classes/';
+				$relativeClassPath = strtr($classNameWithoutVendorAndProduct, (strpos($className, '\\') !== FALSE) ? '\\' : '_' , '/') . '.php';
+				$classFilePathAndName = $extensionPath . $classesRootPath . $relativeClassPath;
 				self::addClassToCache($classFilePathAndName, $className);
 			} catch (\BadFunctionCallException $exception) {