Check your precise subscriber options for that list that "fails" and the
one that works.  E.g., is HTML set on ?

Also it may be that one has a Bottom_Banner set for one of the lists.  In
Digest distributions, that occurs at the TOP!  Banners can sometimes
cause MIME problems.

Also, lately I've been using DIGEST MIME NOHTML under the latest version
of Eudora (5.1.0) and that produces a .MBX attachment.  This is much
nicer than my previous NOMIME digest (a simple compendium).

/Pete Weiss @ Penn State