In the obscure world of copyright law, it is now technically OK to jailbreak an iPhone. That's according to a Library of Congress ruling, which has designated replacing the operating system of the phone with a less restrictive one to fall under the "fair use" guidelines. Fair use is the standard under the Digital Millennium Copyright Act that permits some specific uses of copyrighted material by non-copyright holders. Software programs -- like the iPhone's operating system -- are covered, along with works of art such as music and movies.