Workarounds for blocked port 25 on outgoing e-mail

[Jay Banks]

I have sendmail and popa3d up and running. Is there any way a person could
offer mail service to people on ISPs that block port 25 outbound from their
networks? I have seen solutions that use different ports, but I'm not sure
about doing this with what I have setup on FreeBSD. It seems like you would
just have to monitor port 25 and a predetermined port at the same time, and
then configure mail clients on the blocked network to send to the
predetermined port instead of port 25.

I bet everyone starting to block port 25 outside of their own networks
really put the hurt on people offering POP3 accounts. I know I can't send
e-mail from my own mail server or the POP3 accounts that I pay money for,
from my house because of this. I have to use google's POP3 service because
it uses different ports for smtp.