After looking into this for a while I have hopefully found a solution.
Download the SRPMS for both sox and graveman.
Install libid3tag.devel lame.devel
rpm --force -Uvh sox*
rpm --force -Uvh graveman*
Run graveman and if needed rescan the external programs and you should now have mp3 support - well it workd for me.
For thos you don not wish to rebuild the RPMs I will make them available at:
These files are hosted from my home server so do not expect great download speeds, they are only small though.
Hope this helps.