kernel-2.4.22-1.2135.nptl GPG signature?

[James Jones]

Evidently there's a kernel update, but when I try to fetch it via 
up2date, I get a popup window that says

The package kernel-2.4.22-1.2135.nptl does not have a valid GPG signature.
It has been tampered with or corrupted.  Continue?

and of course, I don't continue.

I could just stick with the kernel I have until FC2, but I'm concerned 
that this should happen. /etc/yum.conf looks at fedora.redhat.com for 
base and released updates, livna.org for stable, unstable, and testing 
packages, and at mozilla-seamonkey for Mozilla (speaking of which, is 
there an Epiphany that plays well with Mozilla 1.5? If not, I may just 
ditch Epiphany). Have others successfully retrieved and installed 
kernel-2.4.22-1.2135.nptl?

    James Jones