Since Fedora 8 reached its end of life, we are not able to get updated packages for pidgin. There are annoying crashes on 2.5.2 (last updated version on Fedora 8) that are fixed on newer releases.
To update pidgin, all we need is install Fedora 7 repository from official pidgin.im site and adapt it for Fedora 8.
wget http://rpm.pidgin.im/fedora/pidgin.repo -O /etc/yum.repos.d/pidgin.repo
sed -i "s/\$releasever/7/g" /etc/yum.repos.d/pidgin.repo
yum update libpurple pidgin