[Nmh-workers] stealthily adding header lines?

[rader]

How do I stealthily add header lines to outgoing mail?  I know about
the components file, but I want to do it after whatnowproc so I
don't see 'em in Editor.  

I traced post and grep'ed on open() came up empty.

If not with nmh, then I'll do it with sendmail, but I'd really like
to do it per-user.

steve
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