Downgrading kernel?

["Oliver Ruebenacker" <curoli gmail com>]

    Dear friends,

 How do I downgrade to an older kernel, or to any older version of an
already installed package? I can not find an rpm or yum option to do
it, and I can not find a yum option to show anything but the newest
version of a package. Thanks!

    Take care
    Oliver

--
Oliver Ruebenacker, Post-Doc Researcher
Theoretical Biological Physics and Soft Statistical Mechanics
Cell Biology at UConn Health Center and Physics at Harvard
http://people.deas.harvard.edu/~oliver/