I've found a DNS A Record for: @domain.com
The IP is not for the mail server (MX records are correct), but it is the IP for the web site. Was this probably put in originally for Squirrel Mail, which is not used and disabled, or for some other reason? And can this A Record be deleted?
The only think left on the server this A Record is pointing to is an FTP site, and it's beeing moved shortly.