Copied this from a news letter I got today, might be of interest
Have You Been Blacklisted?
Recently, in response to our "Caught in the Web" editorial, our reader Paul V. wrote about a different way of getting caught up in the 'Net. It happened to his company and has happened to many other businesses and individuals: you find that other people can't get your email because it's being blocked by their spam filters. You didn't use any questionable words or send pictures or HTML mail or do anything else that would make your message look like spam, but it's still being blocked. Why is this happening?
It might be because your address is on one of the many "known spammer lists" (also called blacklists or black hole lists) that are compiled and used by some spam filtering software. But you aren't a known spammer - you've never sent a spam message in your life! So how did you end up on a blacklist?
Here's the problem: some of the black list organizations will put an ISP's entire domain name on the list because some of that ISP's customers are spammers. When the entire domain is blacklisted, that includes the mail of innocent customers who send mail from that ISP's mail servers, too. What can you do about it if you find yourself in that situation?
You could change ISPs, of course - but that can be a big inconvenience if you've had your address for a long time and it's widely known. You can ask people with whom you want to correspond to configure their "white lists" or "safe senders" lists to allow your mail through; most anti-spam software gives precedence to the white list and allows mail from addresses on it even if those addresses/domains are also on a black list. But if you can't send them mail in the first place, this means you'll have to call each correspondent or send snail mail or contact them in some other way to let them know to do this. Some ISPs use blacklists themselves to protect their users from incoming spam, but this means if you get on the list, you won't be able to send mail to customers of that ISP and the customers themselves may have no control and no way to "whitelist" you so your mail can get through. You're just considered "collateral damage" in the war against spam.
As Paul notes, "being on this black list is bad for our reputation ... if it were any other media, I could probably sue the blacklist company for slander. In this case they don't even respond to my messages ... There should be a way to be protected from the behaviour of blacklist companies if you don't produce spam. A simple way would be to forbid them to blacklist ranges of IP addresses, only those addresses that have been proven to be used for spam."
For a company, being blacklisted is more than just frustrating - it can result in real monetary losses if you're unable to correspond with customers, partners, vendors and others critical to your day-to-day business. For an individual, being blacklisted can interfere with your personal relationships, keep you from getting a job or prevent you from communicating with organizations with which you do business.
One of the first and most popular blacklists was the Mail Abuse Prevention System Real-time Blackhole List (MAPS RBL). It compiled thousands of entries and is used by hundreds of servers all over the world. It was acquired by Trend Micro in 2005. Spamcop.net is another service that takes spam reports and provides a free DNS-based blocking list.
Unfortunately, when it comes to getting blacklisted, you're guilty until proven innocent, and guilt by association (merely having the same ISP as a spammer) is the order of the day for some lists. Black list compilers (also known as DNSBL operators) publish their lists of individual addresses, domain names, or IP addresses without any sort of warranty that those on the list really are spammers. Spamcop, for example, explicitly states on its web site that their list is provided "as is" and they do not in any way guarantee it or take any responsibility for the results of using it:
http://www.wxpnews.com/EWEN8K/080219-Disclaimer
There's nothing regulating the operation of a blacklisting service; all you need is a domain, a DNS server and a list of addresses to publish. Different blacklist operators have different policies regarding how they verify their information, how long an address stays on the list, procedures for challenging the listing and having it removed, etc. Some lists add addresses submitted by users, and it's possible to get on a blacklist just because you made the wrong person mad at you.
Nobody wants to get spam, and the intent of the lists is good, but as with any technology, good intentions aren't always enough to prevent bad results. Intelligent spam filtering requires more than just consulting a list; modern filtering programs such as IHateSpam use sophisticated metrics to examine the content of messages themselves and determine whether they're likely to be spam. This results in far fewer false positives.
What about you? Have you been blacklisted, or have you missed getting email from business associates, personal friends or others because your ISP blacklisted them? Should there be laws regulating blacklists and requiring them to verify that listed IP addresses or domains really belong to spammers? Should people whose mail is unjustifiably blocked by blacklists have recourse to sue and collect damages? Should blacklists be banned altogether, or do they play an important part in combating spam? Let us know your opinions at
feedback@wxpnews.com.