If session.use_cookies is set to off, SquirrelMail
1.4.7 and 1.5.2cvs logins fail.
PHP 4.4.3cvs, 5.1.4, 4.3.10.
session.use_trans_sid = on
session.use_cookies = off
SquirrelMail scripts don't add session id to
redirection headers ('Location: some_url') and <meta>
refresh tags. PHP does not modify them too.
List of known broken scripts:
* src/left_main.php (meta refresh)
* src/download.php (See #1514631)