Still having up2date problems (and yum too)

[Law Barstow]

I am having problems trying to update the packages on my FC2 x86_64
system with either yum or up2date.

[Up2date section]

I resolved the header message by following the advice given on this list
and deleting the header and rpm files from /var/spool/up2date.  Now when
I run up2date -u, the following output is produced (see bottom of
message for yum info):

Testing package set / solving RPM inter-dependencies...
/etc/security/selinux/file_contexts: No such file or directory
########################################
RPM package conflict error.  The message was:
Test install failed because of package conflicts:
The following packages were added to your selection to satisfy
dependencies:
Name                                    Version        Release
--------------------------------------------------------------
xorg-x11-libs                           6.7.0          5
xorg-x11-libs                           6.7.0          5

package xorg-x11-libs-6.7.0-5 is already installed

[root at Linux64 law]#

[Yum Section]

Not wanting to be closed minded, I tried yum. Output is:
[root at Linux64 law]# yum update
Gathering header information file(s) from server(s)
Server: Fedora Core 2 - x86_64 - Base
Server: Fedora Core 2 - x86_64 - Extras
Server: Fedora Core 2 - x86_64 - Released Updates
Finding updated packages
Downloading needed headers
Resolving dependencies
....Unable to satisfy dependencies
Package mozilla-devel needs mozilla-nspr-devel = 37:1.6-8, this is not
available.
Package mozilla-devel needs mozilla-nspr-devel = 37:1.4.1-18, this is
not available.
Package mozilla-devel needs mozilla-nss-devel = 37:1.6-8, this is not
available.
Package mozilla-devel needs mozilla-nss-devel = 37:1.4.1-18, this is not
available.
Package mozilla-devel needs mozilla = 37:1.6-8, this is not available.
[root at Linux64 law]#

BUT.....  

[root at Linux64 law]# rpm -q mozilla
mozilla-1.6-8
mozilla-1.4.1-18
[root at Linux64 law]# rpm -q mozilla-nspr-devel
mozilla-nspr-devel-1.6-8
[root at Linux64 law]# rpm -q mozilla-nss-devel
mozilla-nss-devel-1.6-8
[root at Linux64 law]# 

So those packages are there.. but yum doesnt seem them.  My
/etc/yum.conf file is:
[main]
cachedir=/var/cache/yum
debuglevel=2
logfile=/var/log/yum.log
pkgpolicy=newest
distroverpkg=redhat-release
tolerant=1
exactarch=1
retries=20
exclude=mozilla-devel
[base]
name=Fedora Core $releasever - $basearch - Base
baseurl=http://download.fedora.redhat.com/pub/fedora/linux/core/$releasever/$basearch/os/

[updates-released]
name=Fedora Core $releasever - $basearch - Released Updates
baseurl=http://download.fedora.redhat.com/pub/fedora/linux/core/updates/$releasever/$basearch/

[extras]
name= Fedora Core $releasever - $basearch - Extras
baseurl=http://fedora.linux.duke.edu/fedorax86_64/fedora.us/$releasever/$basearch/RPMS.stable/
#[updates-testing]
#name=Fedora Core $releasever - $basearch - Unreleased Updates
#baseurl=http://download.fedora.redhat.com/pub/fedora/linux/core/updates/testing/$releasever/$basearch/

#[development]
#name=Fedora Core $releasever - Development Tree
#baseurl=http://download.fedora.redhat.com/pub/fedora/linux/core/development/$basearch/


Any suggestions for resolving either the yum or up2date problems?

Many thanks,
Law