Prevent packages from switching from repo to repo

["Benjy Grogan" <benjy grogan gmail com>]

Hello,

Is there a way of preventing a package from updating to a more recent
package from another repo?  I have several repos enabled, and I
noticed today that one package was set to be updated to one from
another repo.  So package foo from Fedora Extras was going to be
updated to a new release ( minor/major version the same though) from
Livna.  Seems like that's almost always unwanted behaviour.  Is there
a way of avoiding these situations with yum, and then in turn possibly
with Pup?

Benjy