relayhost_maps

# Per-sender provider; see also /Library/Server/Mail/Config/postfix/sasl/passwd
# e.g.: <email> [<relayhost>]:<smtp port>
# If you made any changes here, save this file and do 'postmap <maps file>' in command line to create$
teste@gfe-tec.pt [cpanel.ideiasfrescas.pt]:587
teste2@gfe-tec.pt [cpanel.ideiasfrescas.pt]:587
teste3@gfe-tec.pt [cpanel.ideiasfrescas.pt]:587