Windows 7: AT&T (Starbucks) WiFi certificate errors

When I log into the AT&T wifi at Starbucks I consistently get a certificate error. It doesn't matter whether I use IE or Firefox and it doesn't matter what store I'm in. It seems to be system wide. Firefox offers the option to view and install the certificate, but this doesn't solve the problem and the pop-ups persist. It may be that only AT&T can solve this, but I'd like to workaround it if possible. Is there some way I can explain to the browser that the wayport is safe? LOL

Yes there's a way to tell firefox to ignore certificate errors. Hopefully this will help:

Tools > Options > Advanced > Encryption Tab > View Certificates

The AT&T certificate is probably in the servers tab. You should be able to add an exception for it in there.

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I checked and the cert that I thought I was installing is not there. I will try this again tomorrow and see what I can figure out.

Edit...

Here are some screenshots which may help clarify what's going on. I tried installing the cert, but it doesn't show up in any of the categories afterward: