I had a similar problem like this and I think I even posted here about it.

I am running qmail, I needed to add a couple entries to my /var/qmail/control/smtproutes for using road runner's smarthosts for certain domains that complained about this:

aol.com:smtp-server.mn.rr.com
netscape.net:smtp-server.mn.rr.com
hotmail.com:smtp-server.mn.rr.com
rr.com:smtp-server.mn.rr.com
udlp.com:smtp-server.mn.rr.com

Not sure what courier SMTP's smarthost configuration is, might want to check their ML archives.

Josh

On Sun, 28 Dec 2003 21:01:02 -0600
B_o_B <chewbaka at toughguy.net> wrote:

> Sunday, December 28, 2003   @   9:00:41 PM Central Standard Time
> 
> Hi.  I was wondering if anyone had any advice regarding the following
> situation I have with Road Runner.
> 
> I fired up an e-mail server over here this weekend (1st time since I
> have had RR), and cannot send mail to many of the Big Guy(AOL,
> RoadRunner, etc...) mail servers.  I have been able to send mail, just
> the big guys seem to block me.  I receive rejects from their mail
> servers saying my IP address & or server is a residential spam bomb pirate,
> and should be treated like a punk.  Here is one from Netscape/AOL:
> 
> UNDELIVERABLE MAIL
> 
> Your message to the following recipients cannot be delivered:
> 
> <************@netscape.net>:
>     mailin-04.mx.netscape.net [205.188.158.57]:
> <<< 554- (RTR:BB)  The IP address you are using to connect to AOL is a dynamic
> <<< 554- (residential) IP address.  AOL will not accept future e-mail transactions
> <<< 554- from this IP address until your ISP removes this IP address from its list
> <<< 554- of dynamic (residential) IP addresses.  For additional information,
> <<< 554  please visit http://postmaster.info.aol.com.
> 
> & here is one I received from Road Runner while sending mail to an
> account their:
> 
>  UNDELIVERABLE MAIL
> 
> Your message to the following recipients cannot be delivered:
> 
> <**********@mn.rr.com>:
>     kcmx03.mgw.rr.com [24.94.165.192]:
> >>> MAIL FROM:<bob at b-o-b.homelinux.com>
> <<< 550 5.7.1 Mail Refused - 65.27.80 - See
> http://security.rr.com/mail_blocks.htm#security - 20031122
> 
> I have standard Residental Cable Modem Access w/a Dynamic IP.
> I have a host name/dynamic dns (free) service through www.dyndns.org.
> dyndns allows me to setup a MX record for my host on the domain name
> they gave me, so I did.  I am running the Courier mail server (if that
> matters).
> 
> I was wondering if anyone else out their had problems like this, and
> what they did to get around it (if you can get around it).
> 
> I know I could get a real IP from a real ISP, and get a real domain
> name, but all that costs money that I don't have to spend on such
> foolishness for my house at the moment.
> 
> Many Thanks,
> 
> Robert (aka B_o_B) David Felix De Mars
> West Longitude 90' 15' 43"
> http://b-o-b.homelinux.com
> 
> 
> 
> _______________________________________________
> TCLUG Mailing List - Minneapolis/St. Paul, Minnesota
> http://www.mn-linux.org tclug-list at mn-linux.org
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> 

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