On my personal web site I'm using self signed certificates for SSL. These are stored by the browser and everything is fine until the moment they're regenerated. However, when you regenerate them (in the way I do, I'm only changing validity) you could not longer access the site, because the browser still uses the old certificate. In the desktop version of Firefox, I'm just removing the old certificate from Tools -> Settings... -> Advanced -> Encryption -> button Certificates -> tab Servers. Unfortunately, Nokia N900 has user interface only for management of certificates of client authorities. Hopefully, the same user interface as in desktop Firefox is available in it's mobile version. You just have to:
- Open the browser;
- Type chrome://pippki/content/certManager.xul in the address bar;
- Click on "Servers" under "Your certificates" and delete the certificate of your server.