Attempting to create a listserv

Hi there,

I am trying to recreate a page with a listserv type functionality where users can post to a forum on the site and receive updates from the forum via email. They can also reply to the email to reply to the posts on the page. I am using bbpress and bbpress code add-on Reply By Email.

Everything seems to be working week with the current implementation, using Postmark for email routing. However, I have not had the opportunity to dig into the code to figure out how to enable attachments in the email messages either sent or received.

If you could let me know if you have any experience with a system like this one, or even have that functionality baked into an existing plugin that I have overlooked, that would be terrific.