Mail load and rejected connections
As some have been noticing, the increasing spam load has been driving the mail server into defensively rejecting new connections while it processed the crap being fed to it. This makes it difficult for mail client programs to send mail, which don’t queue it up the way other servers do.
For a short term fix, I’ve adjusted the timeouts on sendmail in order to try to cut down the impact of the incoming spam.
The long term solution is to setup a separate server for outgoing mail that won’t be affected by the incoming mail. While the server itself isn’t hard to setup, enabling it to authenticate (i.e. you login to send mail, required to prevent it from becoming a spam relay itself) is a much thornier problem…