edit /path/to/exim_config/configure
at main_config
system_filter_file_transport = address_file
system_filter = /usr/exim/system_filter
system_filter_user = exim
vi /usr/exim/system_filter
if $return_path is “edtai@usnei.net”
then
unseen deliver someone_to_backup_edtai_outgoing_mail
finsh