You can now get up2date working again by downloading
https://rhn.redhat.com/help/RHNS-CA-CERT
and copying it to /usr/share/rhn/RHNS-CA-CERT
I don't think the rawhide up2date has the right certificate yet, so keep a
copy of the RHNS-CA-CERT file in case it gets overwritten by an up2date
update.
Michael Young