Earthlink has decided to clamp down on outgoing spam. This means subscribers will no longer be able to initiate a port 25 connection to any server other than Earthlink mail servers.
• You can still use web-based email
• You can no longer use POP "fetch then send" email accounts without reconfiguring to send via EarthLink (who will evidently monitor for spam or for volume).
• (if you are a spam artist) You can no longer find open mail relays, in the far east for example, and spam the net.
It will be interesting to see if their spam-detectors will throttle or kill home-based mailing-list work.

Text from Earthlink follows:

We wanted to alert you to a new EarthLink policy that should benefit all members but may require you to change one of your email software settings. As you may know, one of the biggest inconveniences to all Internet users is unwanted junk email, or "spam." That's why we have made our Spaminator service available to all members free of charge. But in order to combat the serious, ongoing problem of spam, EarthLink is instituting a new policy called "Port 25 blocking."
WHAT IS PORT 25 BLOCKING?
Port 25 blocking will stop spammers from sending out huge waves of unauthorized junk email by preventing EarthLink email from being sent out through any non-EarthLink mail servers. With Port 25 blocking, anyone logged in to an EarthLink access number will only be able to send mail through the EarthLink mail servers, thereby allowing us to block spam sent out through our network.
DO I NEED TO DO ANYTHING?
If you only use EarthLink to send your email, you won't have to do anything new and can stop reading this alert now. Unfortunately, there could be an inconvenience associated with this new policy if you have a second, non-EarthLink email account.
SECONDARY EMAIL ACCOUNTS
EarthLink will begin Port 25 blocking within the next couple of months. Once this policy is fully in place, any EarthLink member who has a secondary email account that is not an EarthLink account or a Web Mail account, will no longer be able to send email using that secondary account's outgoing (SMTP) mail servers. You will still be able to receive email normally through these accounts, but in order to send email, we need you to make a change for us. (You will also still be able to send and receive email from any Web-based mail system, such as HotMail, without making any changes to your Web settings.)
EMAIL SOFTWARE SETTINGS
In your email software, please change your outgoing (SMTP) mail server for all secondary accounts to the EarthLink mail server: mail.earthlink.net. This will have no impact on how your sent mail appears or on the ability of people to reply to you at your secondary email account. It simply allows EarthLink to ensure that spam is not being sent out through our network of access numbers. Again, in order to use your secondary email accounts normally, as soon as you can, please change all outgoing (SMTP) servers to: mail.earthlink.net.