Problem with yum update

[Truls Gulbrandsen]

When trying to do "yum update" I get the following error message.  
Anyone being able to help me correct this?  "apt-get update" works fine

quote

[root at localhost truls]# yum update
Gathering header information file(s) from server(s)
Server: http-gstreamer.net-pkg-fedora-2-i386-yum-gst
Server: http-redhat.secsup.org-fedora-core-2-i386-os-
Server: http-download.fedora.us-fedora-fedora-2-i386-RPMS.stable-
Server: http-download.fedora.us-fedora-fedora-2-i386-RPMS.updates-
Server: http-gstreamer.net-pkg-fedora-2-i386-yum-deps
Server: 
http-download.fedora.redhat.com-pub-fedora-linux-core-updates-2-i386-
Server: Dag APT Repository
Server: Livna.org Fedora Compatible Packages (stable)
Server: Livna.org Fedora Compatible Packages (unstable)
Server: Mozilla SeaMonkey Realeases
Finding updated packages
Downloading needed headers
Resolving dependencies
.....Unable to satisfy dependencies
Package mplayerplug-in needs mozilla = 37:1.6, this is not available.
Package mplayer-gui needs mplayer = 0:1.0-0.lvn.0.13.pre5.2, this is not 
available.

unquote

Help will be appreciated,
Truls Gulbrandsen