[Exim] Bogofilter and system wide filter

Hello,

I would like to use bogofilter in a system-wide filter, after some
research into archives (results :
http://www.exim.org/pipermail/exim-users/Week-of-Mon-20021125/046767.h
tml
http://www.vmlinuz.ca/archives/exim-users/2002-11/msg00831.html )

I made my own filter but it doesn't work :
# Exim filter

if not first_delivery then finish endif

if error_message then finish endif

pipe "/usr/bin/bogofilter -d /usr2/bogofilter -e -p -l -u"
if $h_X-Bogosity: contains Yes
then
    # save spam in a file
    save $home/.spam
        seen finish
elif $h_X-Bogosity: contains No
then
    unseen finish
endif