Confusing output from YUM on Fedora Core 5
 

I am running Fedora Core on a 32-bit Intel Pentium IV system. I recently ugraded from Fedora Core 4 to Fedora Core 5.

When I launch YUM Extender to see if there are any updates, I get the following output:
Mirrordetection : best
/usr/lib/python2.4/site-packages/yum/config.py:439: DeprecationWarning: getConfigOption() will go away in a future version of Yum.
Please access option values as attributes or using getattr().
DeprecationWarning)
/usr/lib/python2.4/site-packages/yum/config.py:447: DeprecationWarning: setConfigOption() will go away in a future version of Yum.
Please set option values as attributes or using setattr().
DeprecationWarning)
Loading "installonlyn" plugin
Cannot open/read repomd.xml file for repository: livna
failure: repodata/repomd.xml from livna: [Errno 256] No more mirrors to try.
Traceback (most recent call last):
File "/usr/share/yumex/yumex.py", line 230, in on_button
self.action.update_packages()
File "/usr/share/yumex/yumexClasses/yumexBase.py", line 1053, in update_packages
if len( sel ) > 0:
TypeError: len() of unsized object

YUM doesn't list anything that needs to update. I don't know if this is because everything is up to date, or if there are problems using YUM.
What does this output indicate?