If you wish to enable the SPF and DomainKeys records for all the domains hosted on the cPanel server you may use the following one line  scripts.

For enabling spf records use.

for i in `\ls /var/cpanel/users`; do /usr/local/cpanel/bin/spf_installer $i;done

For enabling dkim (domainkeys) records use.

for i in `\ls /var/cpanel/users`; do /usr/local/cpanel/bin/dkim_keys_install $i;done