Index: typo3/t3lib/class.t3lib_div.php
===================================================================
--- typo3/t3lib/class.t3lib_div.php	(Revision 4521)
+++ typo3/t3lib/class.t3lib_div.php	(Arbeitskopie)
@@ -4128,7 +4128,7 @@
 				$xmlContent = t3lib_div::xml2array($xmlString);
 				if (!is_array($xmlContent)) {
 					$fileName = substr($fileRef, strlen(PATH_site));
-					die('The file "' . $fileName . '" is no TYPO3 language file!');
+					die('The file "' . $fileName . '" is no TYPO3 language file!\nReason: ' . $xmlContent);
 				}
 
 					// Set default LOCAL_LANG array content: