spamd fails to start due to missing rules

Symptoms

You see errors like these when you try to start spamd:

spamd[8574]: config: no rules were found! Do you need to run 'sa-update'?

And spamd fails to start up.

Description 

This issue occurs when no SpamAssassin rules are configured.

Workaround

Run /usr/local/cpanel/3rdparty/bin/sa-update, then start spamd with /scripts/restartsrv_spamd.