There is no bug in the system - at least not with my system.
You are using Earthlink as your ISP at home?
If so, using Port 25 should work and if not, use Port 587.
Definitely use Port 587 for the .Mac SMTP server.
My outgoing server settings are, as directed by three tiers of
earthlink support personnel, are:
Regardless what three tiers of Earthlink support personnel directed, use the SMTP server settings that I provided in my previous post.
The only change you need to make is using MD5 Challenge-Response for the authentication type instead of Password.
I've been using these settings for years without any problems - regardless if connected to the internet with my ISP at Home which isn't Earthlink or when using my Earthlink dial-up account when traveling.
I just successfully sent a test email with my Earthlink account using the SMTP server settings provided.