rpm --import http://dag.wieers.com/rpm/packages/RPM-GPG-KEY.dag.txt wget http://apt.sw.be/redhat/el5/en/x86_64/rpmforge/RPMS/rpmforge-release-0.3.6-1.el5.rf.x86_64.rpm rpm -ivh rpmforge-release-0.3.6-1.el5.rf.x86_64.rpm

gem install -v=2.7 mysql -- --with-mysql-lib=/usr/lib/mysql 上手くいかない場合は gem install -v=2.7 mysql -- --with-mysql-config