After a fresh install, when logging in for the first time and getting redirected to the ACP, the following information is being displayed:

[phpBB Debug] PHP Notice: in file /includes/acm/acm_file.php on line 96: Undefined property: vars
HTTP/1.1 200 OK Date: Tue, 13 Jun 2006 08:00:30 GMT Server: Apache/1.3.33 (Win32) PHP/4.3.11 X-Powered-By: PHP/4.3.11 Cache-Control: private, no-cache="set-cookie", pre-check=0, post-check=0 Expires: 0 Pragma: no-cache Keep-Alive: timeout=15, max=90 Connection: Keep-Alive Transfer-Encoding: chunked Content-Type: text/html eaa

The same error sometimes, not always, occurs when switching between "Forum Index" and "Admin Index" several times.