Advice to swithc to xorg from XFree86-4.3.0-59

[Harry Putnam]

Satish Balay <balay at fastmail.fm> writes:

> you should do 'yum upgrade' - and it should take
> care of obsoletes XFree86 -> xorg etc..
>
> If there are more dependency problems - remove packages (with yum
> remove) that are causing the conflicts - and try 'yum upgrade' again

Before you showed me how to set up yum.conf.  I attempted to get it
to go to the right tree by editing /etc/fedora-release.

Now when I run yum upgrade as suggested it errors out on the
release.  

  yum upgrade
  Gathering header information file(s) from server(s)
  Server: Rawhide Development
  Finding updated packages
  Downloading needed headers
  Finding obsoleted packages
  Traceback (most recent call last):
    File "/usr/bin/yum", line 30, in ?
      yummain.main(sys.argv[1:])
    File "/usr/share/yum/yummain.py", line 260, in main
      obsoleting, obsoleted = clientStuff.returnObsoletes(HeaderInfo, rpmDBInfo, nulist)
    File "/usr/share/yum/clientStuff.py", line 286, in returnObsoletes
      rc = rpmUtils.compareEVR((e1, v1, r1), (obe, obv, obr))
    File "/usr/share/yum/rpmUtils.py", line 121, in compareEVR
      rc = rpm.labelCompare((e1, v1, r1), (e2, v2, r2))
  rpm.error: Invalid version or release - possibly None

I tried setting the file back to original state but yum isn't buying
it.  Finally I tried installing the fedora-release in rawhide.

Still yum errors out on release problem.  Finally I tried updating to
most recent yum, but it still errors out on `release'.

Any idea how I can fix that and get on trying the upgrade?