Powermta rate limit outgoing email by domain

Often times you would want to limit your outgoing email from powermta to an specific recipient domain, say example.com. In powermta the way to do this is:

<domain example.com>
max-smtp-out   1
max-msg-rate 1000/h
</domain>

If you want to limit outgoing rate per day, then you can use this:

<domain example.com>
max-smtp-out   1
max-msg-rate 2400/d
</domain>