[Exim] deliver_drop_privilege

Hi all,

I'v a problem to set "deliver_drop_privilege".

On a transport i set:
user=exim
group=users

I compiled exim-3.953 with
EXIM_USER=exim
EXIM_GROUP=

In the /etc/passwd i have:
exim:x:1008:100

and got in the log:
unable to set gid=100 or uid=1008 (euid=1008):
when i set deliver_drop_privilege


any suggestion whats wrong with this setup?

Thank you in advance,

RObert