I too subscribed using mozilla--I had to go over to the radio station to do it because my computer at home (a mac with IE 6) wasn't working with it.....I think it's just a glitch in the site, perhaps resulting from heavy traffic. Presumably they'll work it all out.
I've noticed Mozilla has given me problems at sites like this one, and several other forums I belong 2.
It does not save my log-in, by that I mean, I log in, and then once I've logged in and go in2 a forum, the "log-in" message comes up again, even with cookies allowed for the site.