When you manage more than one domain, or when you have a .local domain as your primary one, a list created with Mac OS X’ Server Admin may show the incorrect domain name.

To fix this, issue:

sudo /usr/share/mailman/bin/withlist -l -r fix_url mylistname –urlhost=mydomain.tld

(replace mylistname with your actual list name and mydomain.tld with the actual domain name)