Last week we mentioned that Earthlink had quietly started redirecting failed DNS queries. A user alerts us that Earthlink has admitted to the change via their blog. It's a quick way for an ISP to make a buck off of your tangled fingers. When DSLExtreme was acquired by Ikano Communications, the new ownership tried something similar, but was forced to back off after ample customer complaints.

According to Earthlink, if a misspelled domain is not owned by anyone, or no longer exists, you'll be redirected to Earthlink's search page. The page directs users to "Please try the related content suggestions and paid advertisements below, or try another search."

"ISP geeks who track of this sort of thing noticed pretty quickly," notes the Earthlink blog, which links to an ongoing conversation in our forums. The entry then clarifies precisely what the service, which was developed in cooperation with BareFruit, is doing:

"It’s important to remember that the Barefruit system only processes errors classified as NXDOMAIN (non-existent domain) when they are in route back to a user’s browser, which means the user experience we are changing is a browser error stating the web site cannot be found or the auto-search functionality of Internet Explorer, neither of which are especially helpful to the user. The system is specifically configured to handle only NXDOMAIN HTTP traffic as it is being returned to the user’s browser and to not impact email and other non-web-browsing traffic."

As our "ISP geek" users note however, this does leave some potential to muck up the functionality of a significant number of network security and anti-spam applications. Most experienced web-users would prefer their ISP leave DNS functionality completely alone. Users here discuss how to change your DNS settings if the new feature annoys you.

In the blog comment section, the Earthlink project manager in charge of the initiative (Ken Womack) states that if "the system ends up negatively impacting users through unintended consequences, that wouldn't be good for EarthLink or our users. In that event, we can simply turn the functionality off."