mail1.sprit.org has one IP number , which also has a corresponding reverse pointer. mail.ugur.at, mail2.sprit.org, mail1.austria-juwel.com and mail2.austria-juwel.com point to the same IP. ksk.at, vs1.at, suf.at, tbl.at, twg.at and at least 100 other hosts use this as a mailserver. sprit.org is delegated to two nameservers, however both delegated nameservers are missing in the zone and two other nameservers are listed instead. There are two duplicated IP numbers. Some of them are on the same IP network. Incoming mail for sprit.org is handled by two mailservers at sprit.org themselves. Two mailservers have the same IP number. sprit.org has one IP number. mail1.sprit.org is hosted on a server in Austria.