andrew long sfajhsdgmailcom wed feb 27 2008 1243 pm jorey bump wrote andrew long wrote 02272008 1147 may slightly offtopic im hoping someone provide clues postfix mta acts selective relay certain ips locations wireless hotspots hotels actual clients guests coming going willy nilly send smtpserver attribute via freeradius understanding spamassassin clamav etc primarily designed process incoming mail local recipients want process mail relayed minimize incidence spam guest laptop becomes infected local spammer manages log wireless someone point right direction clarify understanding isp sprint offer relaying option curious provide smtp relay service would guests ever use seems would useful spammers malware scanning open relays network required upper hotel management group provide relay youre proxying port 25 reconsider puts guests risk exposing login information attempt authenticate using existing configurations email clients blocking port 25 completely reasonable situation long guests use port 587 webmail proxied way implications closing port 25 public terms mtx knowing communicate back mtx understand 587 standard alt port changing something nonstandard andrew fri 08 aug 2008 001545 0500 spam handling relayed mail