Thanks for the support, patrick
My response from Dreamhost was,
"No, we don't offer that. You can just direct someone to the signup form through GNU mailman."
Which is baloney, because it's just a matter of what code is required to get the proper POST submission to get someone signed up, but this is beyond my expertise.
I love Dreamhost, and am happy they provided us with GNU mailman discussion lists at all, much less for free, but would like to be able to add a more "embedded" signup interface. Let's face it, Mailman is awesome, but it's not the greatest UI ever.
chapel hill, nc