Yaakov Stein wrote: > > Would it be possible to post information that would help here ? > What is constant and can be relied upon ? The List-Id works pretty well for me, for example this IETF discussion, announce, and ID announce mailing lists are filtered by procmail using: :0: * ^List-Id: IETF-Discussion <ietf.ietf.org> Mail/ietf :0: * ^List-Id: <ietf-announce.ietf.org> Mail/ietf-announce :0: * ^List-Id: <i-d-announce.ietf.org> Mail/i-d-announce Best, -- Benno _______________________________________________ Ietf@xxxxxxxx http://www.ietf.org/mailman/listinfo/ietf