Safari vs secure sites

[ElyseC]

Safari just today on this computer refuses to allow me to log into sites like my bank, PayPal, and another one I tried. It even goofed up here and won't present me with the list of new/unread messages. Another weird thing about this sudden behavior is that once I try to log into such a site, then (while waiting) call up another tab to get another site loading at the same time, the other site won't load at all. Even Google and Google is the site I use as a test -- if I cannot get to Google, then there's something truly amiss.

I've dumped Safari's .plist and contents of its entire cache folder (should I have dumped the folder itself, too, I now wonder...), but no change. I've quit and restarted the app after every try at an https login, but that doesn't make any diff either. I can go here and there with it, but try logging onto a site and submit my username and password to log in and from there the party's over.

Ideas anyone?

Oh yeah...how am I here typing? Firefox, but I usually use Safari for all but a couple of sites.