CentOS repository does not have PHPMyAdmin. Version on the officall site was changed and we fix this in the next release.
You can install PHPMyAdmin manually after installation by this way
1. Open shell and type two command
Code:
wget -O /tmp/phpMyAdmin.tar.gz http://downloads.sourceforge.net/project/phpmyadmin/phpMyAdmin/2.11.10/phpMyAdmin-2.11.10-all-languages.tar.gz
/usr/local/ispmgr/sbin/pkgctl cache
2. Open ISPmanager Features menu and activate PHPMyAdmin