Today I was very surprised (unpleasantly) with FireFox 2.0 behavior. I would not expect, that I would have to use IE because of some stupid FireFox limitation. Try to go to this link http://nhw.pl:95/wp/ (there is no service on this port). But that was normally domain for IE, which try to know better than user what is good for him.
This address uses a network port which is normally used for purposes other than Web browsing. Firefox has canceled the request for your protection.
Very annoying. And especially this Try Again button ;-)) well URL won’t change with another click.
I say that worst is there is no workaround (at least known for me, but I did not Google a long time, and no network.security.ports.banned.override does not work in FF 2.0).