[CentOS] gnome-desktop on Centos-6.3

I have installed a minimal kvm host system. I wish to provide a graphical login on the host. To this end I performed the following group installs:

yum groupinstall "general purpose desktop" "x windows system"

I can login on the host system as root and then run 'startx' which gives me a desktop, sort of. The top menu bar with the various tool sets is missing as is the lower status bar. I get the same result when I log in as a non privileged user. Am I missing some other package which is required to provide these? I installed gnome-desktop directly but this action produced no visible change in behaviour.