Though I can not help you with your specific instance, there
seems to be an almost innumerable number of ways that designers
of mail systems have botched the implementation of the various
RFCs that specify the meaning of the e-mail fields.  Then again,
sometimes they get it right, but the host sysadmin or user
has a config problem.
 
For the most part, LISTSERV does not try to "correct" the world,
but just co-exist in it e.g., loop-detection, duplicate messages,
commands sent to the list (instead of the LISTSERV).  It provides
various options to ameliorate other difficulties, SAFE=YES|NO.
various SET list options such as DUALHDR, IETF, SHORT822.
 
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