[CentOS] yum install perl-XML-Parser

When I do the following:          yum install perl-XML-Parser

I get all these errors.

Loaded plugins: fastestmirror
Loading mirror speeds from cached hostfile
 * addons: mirror.sanctuaryhost.com
 * base: centos.cs.wisc.edu
 * extras: mirror.trouble-free.net
 * updates: mirrors.serveraxis.net
Traceback (most recent call last):
  File "/usr/bin/yum", line 29, in ?
    yummain.user_main(sys.argv[1:], exit_code=True)
  File "/usr/share/yum-cli/yummain.py", line 309, in user_main
    errcode = main(args)
  File "/usr/share/yum-cli/yummain.py", line 178, in main
    result, resultmsgs = base.doCommands()
  File "/usr/share/yum-cli/cli.py", line 345, in doCommands
    self._getTs(needTsRemove)
  File "/usr/lib/python2.4/site-packages/yum/depsolve.py", line 101, in 
_getTs
    self._getTsInfo(remove_only)
  File "/usr/lib/python2.4/site-packages/yum/depsolve.py", line 112, in 
_getTsInfo
    pkgSack = self.pkgSack
  File "/usr/lib/python2.4/site-packages/yum/__init__.py", line 661, in 
<lambda>
    pkgSack = property(fget=lambda self: self._getSacks(),
  File "/usr/lib/python2.4/site-packages/yum/__init__.py", line 501, in 
_getSacks
    self.repos.populateSack(which=repos)
  File "/usr/lib/python2.4/site-packages/yum/repos.py", line 260, in 
populateSack
    sack.populate(repo, mdtype, callback, cacheonly)
  File "/usr/lib/python2.4/site-packages/yum/yumRepo.py", line 190, in 
populate
    dobj = repo_cache_function(xml, csum)
  File "/usr/lib64/python2.4/site-packages/sqlitecachec.py", line 42, in 
getPrimary
    self.repoid))
TypeError: Parsing primary.xml error: Start tag expected, '<' not found


I tried yum clean all and tried again. same thing.

What do I do?

Jerry