then I've started googling the net and .... ____finally____ I found the magic combination. One very merciful soul posted the golden combination.
yum groupinstall "XFCE-4.4"
It's unfortunate, but I've been tripped up by yum when doing searches. I feel that especially when doing the 'search', 'list', 'whatprovides' subcommands, the search term should be case-insensitive. This is particularly dumb when the package name is upper-case XFCE, but most of the individual rpms are lower-case eg. xfce4-session Maybe a command-line option for this?