I have the problem with untrusted certificates too and none of the FF Help solutions are effective. The time/date thing won't work because I use a VPN that gives me an IP in another time zone sometimes. I need to be able to surf the web with local time on my computer while using a VPN that is connecting thru another time zone. When I use a VPN connection in the same time zone, I don't get the untrusted certs problem, but being behind the GFW I sometimes get bumped after long sessions. Also, when I add an exception for these certificates, "a page" will load, some page, but not at the website I'm trying to access. For example, if I'm trying to access Youtube and add an exception for it, I end up at a completely different website, some weird site that doesn't seem to do anything. AND IT WILL BE THE SAME FOR EVERY EXCEPTION I ADD. When I connect to the Net with an IP addy that matches my actual time zone, I don't have any problems, but this isn't feasible for watching certain videos that require a USA IP or for default language options like at Google that automatically display your "local language." Could be Russian, Chinese, German, etc depending on which VPN server I'm connecting to. The time zone thing needs to be fixed. Maybe you can update FF so it ignores that when using a VPN connection.