It's been quite a while since I've done it, as I've stopped using mint-menu altogether for like 1/2 a year now preferring the standard gnome style menu instead. However, I did have mint-menu installed over on Arch before. Like I said, I don't remember how exactly I did it, it wasn't that difficult though. I believe I extracted the rpm to the default directories and it just worked. Might be worth a try.