Index: typo3/sysext/cms/tslib/class.tslib_content.php
===================================================================
--- typo3/sysext/cms/tslib/class.tslib_content.php	(Revision 7802)
+++ typo3/sysext/cms/tslib/class.tslib_content.php	(Arbeitskopie)
@@ -7016,7 +7016,10 @@
 	protected function isClassAvailable($className, array $config = NULL) {
 		if (class_exists($className)) {
 			return true;
-		} elseif ($config) {
+		} else {
+			if ($config === NULL) {
+				$config = array();
+			}
 			$pluginConfiguration =& $GLOBALS['TSFE']->tmpl->setup['plugin.'][$className . '.'];
 			if (isset($pluginConfiguration['includeLibs']) && $pluginConfiguration['includeLibs']) {
 				$config['includeLibs'] = $pluginConfiguration['includeLibs'];