On a basic Redhat 8.0 installation, php is configured (in /etc/php.ini) to using the handler type "user" ie:
session.save_handler = user;
This is the "handler used to store/retrieve data", which on the http://php.net web site (which is a must, newbies
session.save_handler = ;
And it worked. Be sure to restart your Apache server:
/etc/init.d/httpd restart
The page describing this directive is here:
http://www.php.net/manual/en/ref.session.php#ini.session.save-handler