makemap hash stopped working after sendmail upgrade [by celiawessen]

Mail Service:: makemap hash stopped working after sendmail upgrade
I've upgraded to sendmail v.8.3.15, but anyway, makemap hash stopped working. Therefore, I could not update the db files for /etc/mail/allias.db and /etc/mail/virtusertable.db. The error message told me I did not have the permission to perform makemap hash.
The solution was to make alias.db and virtusertable group writable – where the group is root.