For now (Dec 13 2011), 

Hardcoded in app/controllers/users_controller.php:
    thefile is the file that stores the list of administrators on disk
    $thefile = file("/local/home/dab/public_html/calaccess/cakephp/app/administrators.txt");
    
    
src directory in cakephp/app comes from http://code.google.com/p/google-api-php-client

ALL YOUR ANSWERS FOR GCAL API ACCESS ARE HERE:
http://code.google.com/apis/calendar/v3/using.html


Steps to victory:

1. You need to create the file: cakephp/app/administrators.txt (used in app/controllers/users_controller.php)
2. You need to rename app/src/SAMPLE_config.php to config.php and insert the appropriate keys/values from your google api console.
3. make sure app/cal_tmp is writable by the web server (run setACLs script)

note: app/cal_tmp/refresh_token.txt needs to be created as an empty file first.