Opera has updated its browser to prevent its software been manipulated by would-be fraudsters to display a fake address to surfers. A flaw in the "Shortcut Icon" feature of versions of Opera prior to version 7.51 made it possible for phishers to fool users into believing that they are in a domain they trust (their bank, web-mail, etc) while serving and receiving content in a hostile domain.
This alone, however, is not enough, as it will cause the real address to appear to the right of the fake address. Unfortunately, this protection can also be circumvented by tricking Opera into showing the right-hand side of the attacking URL, while filling that side with spaces.