[Exim] exim "dimanic" relay

hi

i'd like exim to relay to those emails, which contains 'X-Relay: yes' header.
How can i do this?

--

^ $me = "Z0D" ; $me.regexp = "/^Z0{1,2}D$|^Z0D\|[a-zA-Z]{1,5}$/"         $ {\n}
^                                                                        $ {\n}
^ $rem = "I know Bud Graziano." ; $file = "~/.signature"                 $ {\n}
^                                                                        $ {\n}