As-tu tenté quelque chose de ce style :
sudo rpm -Uvh http://redhat.download.fedoraproject.org/pub/fedora/linux/core/5/i386/os/Fedora/RPMS/fedora-release-5-5.noarch.rpm
et/ou
sudo rpm -Uvh http://redhat.download.fedoraproject.org/pub/fedora/linux/core/5/i386/os/Fedora/RPMS/yum-2.6.0-1.noarch.rpm
?