yum - mysql upgrade/install

[bruce]

hi.

i'm trying to configure yum, (if possible) to upgrade/install mysql from the
current FC4 version to mysql-5.0.22.

i can get the mysql RPM from pbone, but i was wondering if i can set yum up
so that yum automatically finds the rpm, and handles the dependency issues.
i've tried to create a yum repos file, but yum seems to complain that it
can't find the 'repodata/repomd.xml' file...

two questions:
 -does anyone have a successful repos file for pbone/mysql
  that i can take a look at.
 -if i simply download the RPM, how can i point yum to the
  rpm, so that yum goes ahead and handles the installation
  and the resolving of the dependency issues..

thanks

-bruce