Open relays and such

[Dave Smith]

I run a mail server on the wild, wild world-of-web (the intarweb, that 
is), and I love it. I have run across a hang up, though. Sometimes email 
I send never arrives at its destination, and I never get a bounce 
message. I'm pretty sure it's not just a case of winding up in the 
end-user's spam folder. What can I do to trouble shoot this? I've 
verified on the top-3 Google responses for "open relay test" that I'm 
not an open relay, so I theoretically should not have wound up on some 
blacklist. What else can I do? Can I check with the big 4 to see if I'm 
somehow being blocked (hotmail, gmail, yahoo, aol)? Any ideas?

Thanks!
--Dave

/*
PLUG: http://plug.org, #utah on irc.freenode.net
Unsubscribe: http://plug.org/mailman/options/plug
Don't fear the penguin.
*/