most internet tests are done by using ping or by using the web server. I am opting that it uses a ping test to e-smith.com. I cannot recall right now the port that ping uses but performing the internet test is not mandatory. a good way to test that the internet connection is working is to login as root using the password you specified for the admin user and use lynx to connect to a website. Don't know the exact setup for your firewall but this should work.
Note: It should work....in theory it does anyway!!
=)