diff --git a/phpgwapi/inc/class.egw_session.inc.php b/phpgwapi/inc/class.egw_session.inc.php
index 38577d587a..5038b81ed7 100644
--- a/phpgwapi/inc/class.egw_session.inc.php
+++ b/phpgwapi/inc/class.egw_session.inc.php
@@ -1661,7 +1661,7 @@ class egw_session
 				}
 				else
 				{
-					header('Cache-Control: public, maxage='.$expire);
+					header('Cache-Control: public, max-age='.$expire);
 					header('Expires: ' . gmdate('D, d M Y H:i:s', time()+$expire) . ' GMT');
 					// remove Pragma header, might be set by old header
 					if (function_exists('header_remove'))	// PHP 5.3+