The overseer of the internet's addressing system rejected for the second time the creation of a ".xxx" top-level domain, supported by some as a way to isolate adult content on the internet.

Nine board members for the Internet Corporation for Assigned Names and Numbers (ICANN) voted against the proposal last Friday at ICANN's 28th International Public Meeting in Lisbon, Portugal. Five voted in favour, while one member abstained from voting, said Andrew Robertson, an ICANN spokesman.

Those rejecting a ".xxx" top-level domain said its creation could set ICANN up as a potential regulator of content on the internet, which is not in its mandate. ICANN is responsible for the administration of the domain name system (DNS), the index that enables the translation of Web site URLS (uniform resource locators) into numerical IP addresses that can be called up into a browser.

ICANN first rejected creating the domain in May 2006. Critics of the new domain said it could make adult content easier to find, but others argued that would also make it easier to filter out with software. The domain also raised concerned over free speech and how content on a Web site may be classified.