They offer a BUSINESS DSL connection that doesn't block said ports.
Bob
With no advance notice SBC began filter port 25 and denying access to all SMTP server addresses except sbcglobal.net.
After nearly a day of trouble shooting, an SBC tech admitted that SBC started filtering port 25 to add their support to fighting spam. They didn't seem to care that their spam-fighting zeal shutdown my company's out-going e-mail for a day.
While they never apologized for blocking port 25 with no notice, they did resolve the issue while I was on the phone. I guess some SBC rocket-scientist figured there was no reason why any subscriber needed to access their own SMTP server. I am constantly amazed at how slowly large companies move until they seize on a really stupid idea.

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