CentOS4にRuby最新インストール
cd /etc/yum.repos.d/ wget http://dev.centos.org/centos/4/CentOS-Testing.repo yum install ruby --enablerepo=c4-testing
cd /etc/yum.repos.d/ wget http://dev.centos.org/centos/4/CentOS-Testing.repo yum install ruby --enablerepo=c4-testing