reduce default session expiration limit

config.php-dist

@@ -125,7 +125,7 @@
 	// *** Cookies and login sessions ***
 	// **********************************
 	
-	define('SESSION_COOKIE_LIFETIME', 86400*30);
+	define('SESSION_COOKIE_LIFETIME', 86400);
 	// Default lifetime of a session (e.g. login) cookie. In seconds, 
 	// 0 means cookie will be deleted when browser closes.
 	// Setting this to zero will affect several user preferences