Hi Psoren,
sail is easy... you just install the latest 2.4.x rpm (if you want DAHDI support). Unfortunately, Asterisk can be very difficult if you don't have the correct kmdl rpms for yor kernel. For that reason we put a section on the wiki to show you how to install and compile asterisk from sources.
It's a pain but there you are, there isn't really anything to be done. The SME folks are always behind on the kernel release (not their fault - its tough just to keep up) and ATrpms keep only the current and -1 kernel versions of their RPMS.
Kind Regards.
S