[CentOS] CentOS 6 and pxeboot

Well, I started the install, got pxeboot to get to the kickstart file,
formatted the drive... and then it failed, telling me "unable to read
group information from repositories. This is a problem with the generation
of your install tree."

A quick google gives me the first hit from a year ago, bug 4372
<http://bugs.centos.org/view.php?id=4372>, which says there's a metadata
problem. Has anyone else run into this today?

       mark