Description of problem:

After a recent yum update, anytihng i do with yum looks something like this:

# yum update
Traceback (most recent call last):
  File "/usr/bin/yum", line 29, in ?
    yummain.main(sys.argv[1:])
  File "/usr/share/yum-cli/yummain.py", line 85, in main
    base.getOptionsConfig(args)
  File "/usr/share/yum-cli/cli.py", line 183, in getOptionsConfig
    errorlevel=opts.errorlevel)
  File "/usr/lib/python2.4/site-packages/yum/__init__.py", line 123, in
doConfigSetup
    startupconf.pluginconfpath)
  File "/usr/lib/python2.4/site-packages/yum/__init__.py", line 227, in
doPluginSetup
    plugin_types, confpath)
  File "/usr/lib/python2.4/site-packages/yum/plugins.py", line 128, in __init__
    self._importplugins(types)
  File "/usr/lib/python2.4/site-packages/yum/plugins.py", line 169, in
_importplugins
    self._loadplugin(modulefile, types)
  File "/usr/lib/python2.4/site-packages/yum/plugins.py", line 185, in _loadplugin
    module = imp.load_module(modname, fp, pathname, description)
  File "/usr/lib/yum-plugins/installonlyn.py", line 23, in ?
    from yum.packages import YumInstalledPackage, comparePoEVR
ImportError: cannot import name comparePoEVR


Version-Release number of selected component (if applicable):

Fedora Core 6 test 2, I don't know how to get version of yum, "yum --version"
gives a similar error.

How reproducible:

Every time.  At least until I get tired of it and reinstall.

Steps to Reproduce:
1. run "yum <command>", such as "yum update" or "yum --version"
2. Watch the stack trace
3. Cry
  
Actual results:
Loss of hair

Expected results:
Beautifying of computer

Additional info:
Well, Initial install of Fedora Core 6 test 2 resulted in Video being all whacky
(defined as : boot screen image was wayyyy too compressed for this
non-widescreen monitor, then X-Windows at the right resoltion (manually set) had
a black square on the top left, so I did a yum update, and that was fixed.  Only
thing: Now yum is broken.