Comcast tells me:

> Thank you for contacting Comcast Customer Security Assurance. We
> have received and reviewed your RBL removal request.
>
> Below each IP address you submitted in your request, we have
> included the result of our research. Please do not reply to this
> message.
>
> 71.126.148.6
> The IP you previously provided has been removed from the
> Comcast.net blocklist.
>
> Our filters have determined that email from the IP you submitted
> was blocked because it sent email to the Comcast domain with
> patterns characteristics of spam. Mail servers are typically shared
> by many users so it may be the case that another party using your
> mail server has sent spam, even if you have not. It is important
> that your email administrator is aware of their outbound spam
> problem to avoid being blocked by Comcast in the future. When
> contacting your email administrator, you should include the error
> message contained in the email which alerted you to this problem.
> Taking this step now will help avoid blocks in the future.

So... You ought to be getting the list messages again.

Thanks to Rob B who kept after me to get this cleared up.

Jim