That 'relative domain' problem is not specific to one-word domain names. In fact, ALL domains that don't end in '.' are considered 'relative' domains. There's a difference between http://somehost/ and http://somehost./ - the first says 'look for somehost in any of the available default domains', while the second says 'look for a top level domain name called localhost'. Likewise http://news.ycombinator.com/ and http://news.ycombinator.com./ are handled differently - the first is actually also considered as a relative URL, and tried against all your local DNS suffixes before being tried against the root.