You posted to the MHonarc mailing list back in November.
in MHonArc, is it possible to list in the index the filename a certain
message was read from?
I think you could have mhonarc remember the name of the input file by:
* have a script look at the msgid's in your input file,
and write a NOTE for each msgid saying which file they came from.
I did something summary with message summaries -- see: