Firefox certificates for Fedora sites?

[Sergio]

Hi. I'm using F18.
When accessing koji.fedoraproject.org, for instance, Firefox has no security certificate for it.
Other pages like Debian sites (a mailing list I accessed yesterday), rpmfusion sites etc. also aren't included in the ca-certificates package (from Mozilla, it seems).

Is it the case that these site owners should contact Mozilla for them to update the certificate bundle or, in the case of official Fedora sites, should an extra package with Fedora certificates be created?