[jhughes@jhughes ~]$ sudo yum list phpMyAdmin Loaded plugins: fastestmirror, refresh-packagekit Loading mirror speeds from cached hostfile * base: 192.168.0.10 * elrepo-kernel: mirror.symnds.com * epel: mirror.symnds.com * extras: 192.168.0.10 * updates: 192.168.0.10 Available Packages phpMyAdmin.noarch 3.5.8.2-1.el6 epel
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This means that phpMyAdmin is in EPEL for EL6.
Do you have an exclude= line in your /etc/yum.conf file?
Do a yum clean all command and try again.