I can't find xmh anywhere in the RedHat 7.2 packages. for i in /auto/rh7.2[xy]/RedHat/RPMS/*.rpm; do rpm -qlp $i | grep xmh > /dev/null && echo $i done only offers exmh, gnome-libs, and pygnome. Let me know where I can find the source to download and compile.
xmh was removed from Red Hat Linux quite some time ago. I believe the last release that it was present in was RHL 6.2. I have no idea where to find the source. Try a search engine perhaps.