I'm using ISPConfig since some jears to manage mail- and webserver, with mostly no conflicts. Now I found some mails in my spamdirectory hosted by an freemailservice. I'v installed drupal. Drupal sends systemmails to that freeservice emailaddress with a strange sender adresse, deliverd by postfix. email@example.com but it should be firstname.lastname@example.org It's fine when mail are send and received through the mailclient but some drupal system mail look like my example. I'm not sure where to look and what to do to get rid off this very ugly virtual-sender-mail-addresses. Hope somebody has an idea.