Beginning this week, the Internet’s “red-light district” will be open for business as the rush for “.xxx” domain registrations starts in earnest, but whether the new tag to alert – and attract – Web surfers to porn sites will meet expectations is a matter of sharp debate.

Some adult-entertainment companies are balking at the entire scheme, saying that ICM Registry LLC, which is overseeing .xxx registrations worldwide, does not have permission to sell the .xxx version of trademarked names and brands.

In addition, the Florida-based company is raising eyebrows – and charges of “shakedown” – by trying to get non-porn companies to pay to prevent their brands from being registered as .xxx sites. After all, what maker of baby food or children’s movies, for example, would want to have sites such as gerber.xxx or disney.xxx floating around the Internet?