[exim] systemfilter permissions

Hi,
I want to move all incoming messages (e.g. from a specific address) to a user defined folder/file.

in my exim.conf I set:
system_filter_user = exim

my filter-file:
# Exim filter
if $header .....
then
save /home/user/mail/file
finish
endif

all works, but there´s a permission problem! changing the permissions to

chown -R user:exim /home/user
chmod g+rw /home/user

chmod exim:user /home/user/mail/file
chmod g+rw /home/user/mail/file

works. when exim is not the owner there´s an error about bad owner id!
but after awhile (next run?) exim changes the permissions of /home/user/mail/file to 600 and I can´t read the mails!

can u help?

        
---------------------------------
Gesendet von Yahoo! Mail - Jetzt mit 100MB kostenlosem Speicher