From: Steve Clark <sclark@netwolves.com>

  

I realize that uname is missing as well as  /sbin/new-kernel-pkg. That is why
I was asking if someone has a "recipe" for  building a kernel from 
"kernel.org" that will install correctly from a  respin.
    

You need mkinitrd and coreutils packages...
Not sure at which step it fails since you did not give details.
Anyway, google says: http://wiki.centos.org/HowTos/Custom_Kernel
Hope this helps...

JD