[exim] Exim -bS problem

Hi,

I'm trying to pipe email into this script:

/bin/grep -v X-SPF-Sucks | /bin/sed -e 's/^MAIL FROM:<.*>$/MAIL
FROM:<spfsucks@???>/g' | /usr/sbin/exim -bS

The email vanishes when I try this. If however I run it out to a file
can then cat the file from the command line through the same filter it
works. Not sure what I'm doing wrong.

Thanks in advance

spf_sucks_deliver:
driver = pipe
command = /etc/exim/scripts/spf-sucks-deliver
delivery_date_add
envelope_to_add
return_path_add
use_bsmtp
group = root
user = root