According to the TM Net Latest News, Telekom Malaysia Berhad is blocking all SMTP traffic or port 25 for all out going emails from dynamic IP addresses.
Due to the spamming activities by a small group of users, many anti-spam organizations have blacklisted a large number of IP addresses from TM’s network.
As a result, many TMNet users unable to send emails from their private mail server to companies who might using the database from the anti-spam organizations.
Effective 3rd December 2007, TM will block SMTP traffic or Port 25 for all out going emails from dynamic IP addresses. Only outbound SMTP traffic from smtp.streamyx.com and smtp.tm.net.my will be allowed.
For TMNet users who have their own email server, they will not be able to send emails from now on. To solve the problem, TM is providing an open relay server for these users who use dynamic IP addresses: smtp-proxy.tm.net.my
My two cents
With the SMTP or Port 25 blocking, we are no longer to setup own email server to send emails via direct connection. Though, the changes does not affect most users but, for advance users, now we have one less usefulness of fast Internet connection.
I used to send out emails to my mailing list using direct connection for faster mail delivery, now I can’t do it anymore…
Update: Many local web hosting providers have updated their mail server (e.g. mail.domain.com) port from 25 to port 26. While hosting server using static IP address is not affected, but their hosting clients using Port 25 to connect to their hosting mail server to send emails.
Therefore, hosting clients are advised to change port number to 26 to skip the Port 25 blocking. The hosting mail server with static IP address is not affected and still use Port 25 to send out users’ emails.