One of my sites gets frequently visited by this refferer: 172.19.1.48:15871/cgi-bin/afterWorkOptions.cgi?ws-session=3944073639 It stays up to an hour on the site visiting many pages.. Is anyone familiar with this? What is that cgi for?
That IP belongs to ICANN ("Internet Corporation for Assigned Names and Number ") - the guys who organise all the tlds like .com, .net, .org I'm guessing someone inside ICANN has visited your site from a link om their own internal intranet(?). Mind, that's all a guess.
Actually that ip is reserved for private use, so its coming from someones internal network. Your site is probably blocked during business hours by some kind of surf control or websense server.