Shaw is now blocking OUTGOING port 25 (SMTP) to anything except their own mail server (shawmail.wp.shawcable.net). This is similar to what MTS did about a year ago.
This is only affecting one of my customers right now, so you may or may not be affected already. The Shaw rep says that it should be affecting all non-business-class customers. Obviously that's baloney because my personal home system still has working port 25 access.
Incoming port 25 appears to be open (unlike MTS which for some retarded reason thinks incoming port 25 is a spam risk).
As when MTS did this, I think it's complete nonsense and a clear example of net bigotry. Complain to your Shaw rep today!