Don't have an answer for you, but I can say that the following URL works under FF-8.0
http://0x12.0x12.0x12.0x12/ (resolves to 18.18.18.18) However, if you force browsers through a squid proxy, squid-2.6 at least treats that as borked and won't play with it. So even proxies are out of step with FF. Don't care if it's "right", there's no need for any browser to accept crap like that :-( It's probably "safe" to have a rule to score such urls - except when they're http://0x12.0x12.com/ or the like! -- Cheers Jason Haar Information Security Manager, Trimble Navigation Ltd. Phone: +1 408 481 8171 PGP Fingerprint: 7A2E 0407 C9A6 CAF6 2B9F 8422 C063 5EBB FE1D 66D1