SelfSSL和Firefox 3的问题

I have a IIS website with a security certificate setup using SelfSSL (part of the IIS Resources toolkit). The certificate appears valid when I view it in ISS and it works fine for IE, Safari and Google Chrome. However, in Firefox 3 it does not consider the certificate valid and therefore shows a certificate warning when you view a secure page on the website.I have a IIS website with a security certificat