Dear Maintainer,
the setting "mail sent by smarthost; no local mail" is not correct. It
promises 'no local mail', but later is says: "The local hostname
(the_name_of_host) and 'localhost' are always added to the list given
here." So even if I choose dc_eximconfig_configtype='satellite' and
dc_other_hostnames='' it will populate local_domains with '@' and
'localhost' and such letters will be frozen locally.
The only way I found to fix is to clean MAIN_LOCAL_DOMAINS in
localmacros file.
The solution I see is to replace dc_other_hostnames with dc_hostnames
and add '@' with 'localhost' by default here. So the old behaviour will
be kept, but it will be customizable from the package configuration.