The RIPE NCC uses greylisting on its mail servers in order to reduce the amount of spam recieved.
Greylisting works by sending a temporary SMTP error the first time an email is received from an unknown sender. Any legitimate mail servers that receive this error will resend the email successfully. The bulk mailers used by spammers do not usually try to resend e-mail that is returned and so the spam is blocked on the first and only attempt at delivery.
Legitimate emails to the RIPE NCC should not be affected by greylisting. However, if you have any problem sending email, please contact [email protected].
If an email address subscribed to a RIPE mailing list bounces five messages from the list server, it will automatically be set to "disabled". This means that the disabled email address will not be sent any of the messages posted to the relevant mailing list.
An automatic notification alert will be sent to the email address in question, though a malfunctioning mailbox may not receive this notification.
Anyone affected by this can reenable their subscription by visiting the membership management page.
When you reach the mailman list info page, enter your email address in the text input box at the bottom of the page, under the "Unsubscribe and other options" heading.