Johann Schubert writes:
>^ is the begining of the line... Since the header tag is at the begining, "Sub
>ject:.*^martin" will never match. Try "Subject: martin"

That makes perfect sense. I was forgetting that the header is
still part of a line and that the RE doesn't care one bit whether that
word is Subject: or Substandard_fungus or anything else. Thank you.