[Tfug] My mail domain is being blocked!

[Cory Hollingsworth]

I have just discovered something sad.  I have been running my own mail
server since 2002 (Linux/Postfix) and both GMail and the PLUG mail list
are blocking my mail server.  In both cases my mail server cannot connect
to port 25 for either domains.  However both will happily send mail to my
mail server.  What hypocrisy! 8-)

This worked some time in the last 6 months, just now I have noticed that
my email has stopped going through.

My mail server IP is not on any SPAM list as far as I can find.  I used
http://www.mxtoolbox.com/SuperTool.aspx to check.  If someone knows of a
better tool please let me know.

Also I have verified that my A, MX, and PTR (reverse lookup) DNS records
are all correct.  They all seem fine.

My mail logs show pretty clearly that my server has never been SPAMing and
all of my open relay tests fail.  I am pretty sure I have the mail server
properly secured.

My mail server has a static IP address, but I am suspecting that GMail and
PLUG may mistakenly believe it to be a dynamic address.  I believe some
places block dynamic addresses.  I wonder how one goes about fixing a
problem of someone misidentifying your IP address as dynamic when it is
static?  Or how does one go about fixing an arbitrary block by a mail
domain?

Any advice on this topic would be welcome.

Thanks.