Remove RPATH code though. Discussions on nmh-workers have convinced me.

Remove RPATH code though. Discussions on nmh-workers have convinced me.

[2012-01-05] Lyndon Nerenberg:
> [2012-01-05] Ken Hornstein:
>> RPATHS    - Construct Return-Path headers from "From " lines.
>>             I say keep it, since it's been around forever (a fair
>>             amount of code, actually).
> I'm going to argue for the removal of this code, as well. The
> Return-Path header should be inserted by the delivering MTA, and I
> can't think of any modern MTA that doesn't.