[exim] file permission in maildir new

Hello,

I have a maildir where I have set file permission set to 770.
Inside there is a "new" folder with also 770 file permission.

When I get a mail the new file has only 600.
How can I solve this?

I use Exim4.
umask is 0022.
I do not use ACL.

Regards,
basti