spam4.smarsh.com has one IP number , which also has a corresponding reverse pointer. 1db.com, 4123.com, swrw.com, pwco.com, hwcm.com and at least 100 other hosts use this as a mailserver. smarsh.com is a domain controlled by five nameservers at tzo.com. All of them are on different IP networks. Incoming mail for smarsh.com is handled by two mailservers at smarsh.com themselves. They are on different IP networks. smarsh.com has one IP number. spam4.smarsh.com is hosted on a server in United States.