Ruffpack, Fedora and "advanced package" with YUM

[Winnie]

Hi,
I would like to know of it is possible to install package like Firefox 
or Evolution 1.5 on Yellow Dog Linux.
If yes, how ?
I know that Ayo and freashrpm can provide package view YUM version 2.
I can read on file yum.conf : ruffpack. I know that is the developpment 
tree of YDL. But how provide package ? NEW package. I can image to use 
Evolution 1.2 on may 2004.
Can you answer my questions ?

PS : Sorry for my horrible english ;-)