Configure your Wordpress Apache server like this to get a response log (do not use the request log...)
<IfModule log_config_module>
LogFormat "%h %l %u %t \"%r\" %>s %b <strong>\"%{set-cookie}o\"</strong>" common2
CustomLog "logs/private/wp_cookie_log" common2
</IfModule>
These logs will be read by wp-cookie-tail to implement a very simple single sign on system when used in conjunction with wp-cookie-verify.