We are happy to make your e-mailing experience even more secure. From now on, our mail servers will be adjusted not to receive mail from mail servers whose hostnames do not resolve back properly by a reverse DNS lookup of their IPs.
This security restriction will prevent your mailboxes from receiving spam and junk e-mails because most of the spammers send mail from random addresses on servers which do not resolve back the correct hostnames. The reverse DNS lookup of the sender’s IP will also decrease the needed time for the messages to be delivered to your inbox and will generally improve your privacy.
UPDATE: The reverse DNS check for e-mails sent to e-mail addresses on our web hosting servers has been disabled.