Index: t3lib/extjs/class.t3lib_extjs_extdirectapi.php
===================================================================
--- t3lib/extjs/class.t3lib_extjs_extdirectapi.php	(Revision 10210)
+++ t3lib/extjs/class.t3lib_extjs_extdirectapi.php	(Arbeitskopie)
@@ -97,7 +97,8 @@
 		$expireDate = date('r', $GLOBALS['EXEC_TIME'] + 3600 * 24 * 30);
 		header('Expires: ' . $expireDate);
 		header('Cache-control: public');
-		header('Pragma:');
+		header_remove('Last-Modified');
+		header_remove('Pragma');
 
 			// return the generated javascript API configuration
 		if (count($javascriptNamespaces)) {