enabling xinetd through systemd

In trying to set up a custom network service under Angstrom, I ran into the fact that xinetd doesn’t automatically start at boot time. Some digging showed that /etc/systemd/system/xinetd.service is just a link to /dev/null.

That’s referred to on this page, apparently in relation to the eMMC: http://www.crashcourse.ca/wiki/index.php/BBB_software_update_process

Unfortunately, all the page says is, “I’ll explain this part at some point:”

I assume there’s some kind of conflict that’s difficult to resolve by other means, but is it possible to enable xinetd at boot through the systemd interface? If not, what fallback mechanism does Angstrom offer for starting things at boot time?