after each install/reconfigure: warning: database /var/lib/mailman/data/virtual-mailman.db is older
After every reinstall or reconfigure (also latest RC 3.0.5.4rc2) I have this in my logs:
postfix/smtpd[31049]: warning: database /var/lib/mailman/data/virtual-mailman.db is older than source file /var/lib/mailman/data/virtual-mailman
postmap /var/lib/mailman/data/virtual-mailman seems to solve it every time.