I'm going to join the hoards of other people in criticizing the latest changes in firefox regarding their stance on self-signed certificates. Also putting in mention on the absurbness of the about:config page. Really guys, what were you thinking?

You can atleast fix the SSL error on the self signed certs by setting the following settings in your about:config..

browser.ssl_override_behaviour = 2
browser.xul.error_pages.expert_bad_cert = true

The first first line will start the error page in "expert mode" (heavy airquotes in usage here), so that you have access to the button to "add a security exception" and add the site's certificate.

The second line will prefetch the certificate for you, speeding up this ugly painful process for you... slightly.