[clue-tech] So-called "smart" hosts.

[T. Joseph Carter]

Okay, now that I am using Comcast for connection purposes, I have
discovered an old pet peeve of mine: Discrimination based on connection
class.  I have a valid IP, I have valid DNS, and I have a valid mailserver
at the IP with the appropriate DNS entry.

At least two major sites refuse my email because I am not using Comcast's
so-called smarthost.  Now, I'm paranoid about my email.  I want to know if
my mail is delivered or not, first of all, and I don't necessarily trust
Comcast nor any other ISP whose admins I do not know and trust at least by
reputation to not lose my mail, in either direction.

Any suggestions, besides seeking professional assistance regarding this
paranoia of mine?  ;)