Other PKI Users, associated with the administrator and auditor groups, can be regular users rather than system accounts. When creating new users, always use the system tools, like useradd or the UI tools, because those automatically update all system files related to users, including /etc/passwd, /etc/shadow, /etc/group, /etc/gshadow, /etc/default/useradd, /etc/skel, and /etc/login.defs.

The process and options for adding users is described in the Red Hat Enterprise Linux 5 documentation at http://docs.redhat.com/docs/en-US/Red_Hat_Enterprise_Linux/5/html/Deployment_Guide/s2-users-add.html. When users are created, they can simultaneously be associated with a group using the -g option. For example, this creates a jsmith user who belongs to the pkiadmin group, and then creates the user password:

# useradd -g pkiadmin -d /home/jsmith -s /bin/bash -c "Red Hat Certificate System Administrator" -m jsmith

# passwd jsmith
New password:
Re-enter new password: