This may not be the place to ask this question, as the usual suspects---ZoneAlarm, box.net, and Mozilla---have forums of their own for these kind of questions. But I've emailed support at ZA and box with no luck. Each point fingers at the other.
I am clueless what to do. As I said in the post title, I have no problems accessing the site in Chrome. So the sherlock holmes in me says that FF is the culprit, but how to make the changes suggested in the link above? And from a security standpoint, do I want this? Could this "open the dam" to other potentially harmful sites too?