According to #exim/irc.freenode.org, this should also work. See (11.9 Expansion variables of the spec) of the manual:
accept recipients = [EMAIL PROTECTED]
deny hosts = !+debianhosts
condition = ${if [EMAIL PROTECTED]
def:h_X-PTS-Approved:{false}{true}}}{false}}
message = messages to the PTS require an X-PTS-Approved header
--
Please do not send copies of list mail to me; I read the list!
.''`. martin f. krafft <[EMAIL PROTECTED]>
: :' : proud Debian developer and author: http://debiansystem.info
`. `'`
`- Debian - when you have better things to do than fixing a system
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