Deleting old "sess_..." files from /tmp dir

Hello, We're trying to use session variables to store a user's database login information. I am wondering how to automatically delete the old "sess_..." files from the /tmp directory which are used by PHP to store session variables. Is there a way to set PHP to do this? I've tried setting the "session.gc_maxlifetime" in the php.ini to a lower number, but had no luck. I suppose a last resort is a script that runs in cron to delete the old files. Our environment is: Solaris 7, PHP 4.1.2, Apache 1.3.22. Thanks in advance for any advice you may have. Tim Haak