Recent versions of mailman (I think both 3 and 2) have a built-in option
to do the from rewriting for mail from domains which have p=quarantine
or p=reject.

I don't know which version mailinglists.dyne.org uses, but it should not
be too much work to enable such re-writing.

-JimC (who uses p=none so that list postings work :)
-- 
James Cloos <cloos@???>         OpenPGP: 0x997A9F17ED7DAEA6