>>>>> "AL" == Andrew Lare <firstname.lastname@example.org> writes:
AL> email@example.com: "David O'C Starr" <starr@climate-f> is
AL> not a valid return address.
That address is unqualified. Since Majordomo is designed to serve mailing
lists to the Internet and unqualified addresses are completely meaningless
outside of the one domain where they work, Majordomo rejects these
addresses. Your log should have a record of the complaint.
Some software (probably your MTA) is ill-configured. It should be adding
the domain to the address. It is possible to disable the check in the code
if you absolutely must allow this (bad) behavior. Let me know if you want
to know where.