The best fix would be making the server check every single action you make, to prevent things like this.
Now, this isn't done, and if Zanz intend it to be so (to make it easier to play with a bad connection, to make the game more smooth, because the server wouldn't be able to handle it, because he doesn't have the time...). I've no idea why not, but certainly there's better ways to spend your time than "hack" things just because you can.
Just because doing something bad is easy doesn't mean you should do it.
