I updated my PKGBUILD file and submitted it to the Arch User Repository, if anyone is interested. It is the 2.5.1 version of Rivendell
Let me know if you are having any issues. For now, I am having trouble with rdcartslots: it will not run at all. Maybe someone can help me out. I have not done thorough testing, but most everything else should work correctly.
-- Sébastien Leblanc