FF doesn't like certain java/php script in it. If something is "broken" within the coding, it doesn't like it either. However, with that being said, I have never received this error when going to RM on FF myself. Usually, this indicates something within your host file showing up in FF's security.
Or you could just ask me! It appears to be your trend micro that is causing it. I have never ever had this problem using a variety of security programs. The only place you put any secure info is on the checkout page(your paypal login, no cc numbers etc) and that is a paypal server.
Can you take screen shots and email them to me at email@example.com. Are you typing the address in or clicking a link?
It is being redirected twice. Once by anonym.to which is planted tank and once by bit.ly which is very reputable. Both are safe redirects. I am having google crawl and norton as well. There is no security risk in the site or links to it, so it seems odd for it to cause this type of reaction.