Greylisting in action, please come back later.

Om spammers nog verder te ontmoedigen is er vandaag zgn. greylisting ingesteld op onze mailserver.

Greylisting (or graylisting) is a method of defending e-mail users against spam. A mail transfer agent (MTA) using greylisting will "temporarily reject" any email from a sender it does not recognize. If the mail is legitimate, the originating server will, after a delay, try again and if sufficient time has elapsed, the email will be accepted. If the mail is from a spammer it will probably not be retried since a spammer goes through thousands of email addresses and typically cannot afford the time delay to retry. (Wikipedia)