I don't know.
It's a highly modified version of phpbb3, but that shouldn't affect emails. The IP address was blacklisted at one time, but if that is the case (server using an old list) you shouldn't get ANY emails.
You can set up an RSS feed as far as I know, which might be a work around. You can also post this issue in phpbb.com forums and see if someone has an idea... I don't have time to track it down right now, but if you learn anything that sounds relevant let me know.
If nothing else ask again in January... PM or email me directly so I won't overlook it.