Index: class.tx_install.php
===================================================================
--- class.tx_install.php	(revision 9510)
+++ class.tx_install.php	(working copy)
@@ -6552,6 +6552,7 @@
 				break;
 			case 'performUpdate':	// third step - perform update
 				$title = 'Step 3 - Perform updates';
+				$databaseQueries = array();  // init variable as array (for following implode)
 				$performUpdateSubpart = t3lib_parsehtml::getSubpart($templateFile, '###PERFORMUPDATE###');
 				$updateItemsSubpart = t3lib_parsehtml::getSubpart($performUpdateSubpart, '###UPDATEITEMS###');
 				$checkUserInputSubpart = t3lib_parsehtml::getSubpart($updateItemsSubpart, '###CHECKUSERINPUT###');
@@ -6603,7 +6604,7 @@
 										FALSE
 									);
 								}
-							}
+							} 
 
 							if (strlen($customOutput)) {
 								$content.= '<br />' . $customOutput;