More precisely, it works until v8.1, in v8.1 "-mport" is working in read-only mode by default, check "History.txt" file for details. Another thing required for this "exploit" is direct access to internet for the system, it will not work via NAT or firewall without your permission.
Later versions had another issue that was fixed too, see my message:
https://bitcointalk.org/index.php?topic=1433925.msg28540417#msg28540417