[root@rails ~]# yum update
error: cannot open Name index using db3 - Cannot allocate memory (12)
Setting up Update Process
Setting up repositories
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 97, in main
    result, resultmsgs = do()
  File "/usr/share/yum-cli/cli.py", line 477, in doCommands
    return self.updatePkgs()
  File "/usr/share/yum-cli/cli.py", line 955, in updatePkgs
    self.doRepoSetup()
  File "/usr/share/yum-cli/cli.py", line 71, in doRepoSetup
    yum.YumBase.doRepoSetup(self, thisrepo=thisrepo)
  File "__init__.py", line 225, in doRepoSetup
  File "repos.py", line 533, in baseurlSetup
  File "repos.py", line 842, in getMirrorList
  File "/usr/lib/python2.3/site-packages/urlgrabber/grabber.py", line 583, in urlopen
    return default_grabber.urlopen(url, **kwargs)
  File "/usr/lib/python2.3/site-packages/urlgrabber/grabber.py", line 741, in urlopen
    return self._retry(opts, retryfunc, url)
  File "/usr/lib/python2.3/site-packages/urlgrabber/grabber.py", line 702, in _retry
    r = apply(func, (opts,) + args, {})
  File "/usr/lib/python2.3/site-packages/urlgrabber/grabber.py", line 740, in retryfunc
    return URLGrabberFileObject(url, filename=None, opts=opts)
  File "/usr/lib/python2.3/site-packages/urlgrabber/grabber.py", line 893, in __init__
    self._do_open()
  File "/usr/lib/python2.3/site-packages/urlgrabber/grabber.py", line 960, in _do_open
    fo, hdr = self._make_request(req, opener)
  File "/usr/lib/python2.3/site-packages/urlgrabber/grabber.py", line 1059, in _make_request
    fo = opener.open(req)
  File "/usr/lib/python2.3/urllib2.py", line 326, in open
    '_open', req)
  File "/usr/lib/python2.3/urllib2.py", line 306, in _call_chain
    result = func(*args)
  File "/usr/lib/python2.3/site-packages/urlgrabber/keepalive.py", line 211, in http_open
    return self.do_open(HTTPConnection, req)
  File "/usr/lib/python2.3/site-packages/urlgrabber/keepalive.py", line 238, in do_open
    self._start_transaction(h, req)
  File "/usr/lib/python2.3/site-packages/urlgrabber/keepalive.py", line 313, in _start_transaction
    h.putrequest('GET', req.get_selector())
  File "/usr/lib/python2.3/httplib.py", line 667, in putrequest
    self.putheader('Host', self.host.encode("idna"))
LookupError: unknown encoding: idna