I've got to say, I'm really quite confused. I have just reread the bugs, and this thread, and I cannot tell if Mailman is going to install on 8.0 or not, or it the basic issue will be resolved or not.
I got it working on 7.51 by downgrading the mailman rpm to an earlier version, as suggested. If I follow the installation procedure from the wiki on 8.0, the smeserver-mailman package is not found, and to get mailman to work, you have to configure some files that appear to be set up by templates.
If the old smeserver-mailman rpm can be installed locally, I would be happy to do so. Some clarity would be appreciated.