There is the mail_max_userip_connections setting, which helps for dealing with number of connections at any given time, but I'm looking for something that will help deal with users who configure their mail clients to connect too frequently.

For example, I've seen users who configured their clients to check (IMAP) mail every 3 seconds. This is far too frequent and puts unnecessary load on the server. Even once per minute seems excessive to me.

It would be really great if there were a way to tarpit those users to slow them down, or send them an imap message saying they are connecting to often and connections have been disabled for the next 5 minutes or something.

Micah

ps - what happens to a user when they hit mail_mx_userip_connections? Further connections are just denied, or dropped?