Description of problem:
Hi I installed FC3 in my office and home PCs and a few weeks ago yum
haven't been working due to some kind of network problem.

At home it works well (I'm not using a proxy).
At the office I have 3 computers with FC3 and all of them fails to
execute yum.  The thing is that it was working and I managed to pull
some updates.  The computers are 2 workstations and 1 production server.

I have the $http_proxy configured like this:
http://williama_lovaton:<password>@192.1.4.140:8080

Every single program that needs to connect to the internet works fine
(eg. wget).  Even yum used to work fine with this.

It fails with every command, for instance I do this:
[root@nalwalovaton ~]# yum check-update
Traceback (most recent call last):
  File "/usr/bin/yum", line 7, in ?
    yummain.main(sys.argv[1:])
  File "/usr/share/yum-cli/yummain.py", line 51, in main
    base.getOptionsConfig(args)
  File "/usr/share/yum-cli/cli.py", line 134, in getOptionsConfig
    self.conf = yumconf(configfile = yumconffile, root=root)
  File "/usr/lib/python2.3/site-packages/yum/config.py", line 327, in
__init__
    self._doFileRepo(fn)
  File "/usr/lib/python2.3/site-packages/yum/config.py", line 399, in
_doFileRepo
    doRepoSection(self, repoconf, section)
  File "/usr/lib/python2.3/site-packages/yum/config.py", line 413, in
doRepoSection
    mirrorurls = getMirrorList(mirrorlist)
  File "/usr/lib/python2.3/site-packages/yum/config.py", line 500, in
getMirrorList
    content = fo.readlines()
  File "/usr/lib/python2.3/site-packages/urlgrabber/keepalive.py",
line 391, in readlines
    line = self.readline()
  File "/usr/lib/python2.3/site-packages/urlgrabber/keepalive.py",
line 376, in readline
    new = self._raw_read(self._rbufsize)
  File "/usr/lib/python23.zip/httplib.py", line 409, in read
    s = self.fp.read(amt)
  File "/usr/lib/python23.zip/socket.py", line 301, in read
    data = self._sock.recv(recv_size)
socket.error: (104, 'Connection reset by peer')


This is my yum.conf:
[root@nalwalovaton ~]# cat /etc/yum.conf
[main]
cachedir=/var/cache/yum
debuglevel=2
logfile=/var/log/yum.log
pkgpolicy=newest
distroverpkg=redhat-release
tolerant=1
exactarch=1
retries=20
obsoletes=1
gpgcheck=1

# PUT YOUR REPOS HERE OR IN separate files named file.repo
# in /etc/yum.repos.d


This is my /etc/yum.repos.d/fedora-updates.repo:
[root@nalwalovaton ~]# cat /etc/yum.repos.d/fedora-updates.repo
[updates-released]
name=Fedora Core $releasever - $basearch - Released Updates
#baseurl=http://download.fedora.redhat.com/pub/fedora/linux/core/updates/$releasever/$basearch/
#baseurl=http://fr.rpmfind.net/linux/fedora/core/updates/3/i386/
mirrorlist=http://fedora.redhat.com/download/mirrors/updates-released-fc$releasever
enabled=1
gpgcheck=1


I'll attach an strace later.