better email address validation
It would be nice if sympa didn’t let you add things that aren’t email addresses. There is a nice perl module that could probably used for doing this Email::Valid. It does a bunch of different checks, probably the ones that would be appropriate would be -fqdn, -local_rules, and -tldcheck. I don’t think -mxcheck could be used as we can’t count on things resolving at add time (although maybe it could warn “hey this address might not work!”). These checks would need to apply for all the ways addresses can be added, user sign up, list admin add, etc.
(from redmine: created on 2010-03-08, closed on 2014-07-03)