[CentOS] (re)load new kernel with rebooting host node?

Hi all,

Is it possible to reload the dom0 / host node's kernel with a newer
one, without rebooting the server? I know kexec can do something like
this for security patches, but I don't know much about kexec, and I
don't want to mess up a production server either. So, has anyone done
something like this before? I need to load a new kernel for one of the
domU's iptables to work, but don't want to reboot the whole server and
cause downtime for the other domU's.

-- 
Kind Regards
Rudi Ahlers
CEO, SoftDux Hosting
Web: http://www.SoftDux.com
Office: 087 805 9573
Cell: 082 554 7532