what's the real meaning of MISSING_SUBJECT ?
should it match without the Subject: header, or even message with empty
Subject: header?

the description says it's about missing subject header, but it seems to
match even when there's "empty" line containing the string "Subject: "
in headers.

Matus UHLAR - fantomas, uhlar@fantomas.sk ; http://www.fantomas.sk/
Warning: I wish NOT to receive e-mail advertising to this address.
Varovanie: na tuto adresu chcem NEDOSTAVAT akukolvek reklamnu postu.
I just got lost in thought. It was unfamiliar territory.