Firefox blocks my firefox in hoary ubuntu

[Jesús Gascón Gómez]

>From time to time and randomly, when I visit some websites with Firefox,
everything in gnome gets freezed, and I have to reset my computer.

Has anybody the same problem? Should I see firefox' logs in case I find
there the problem? 

How can I find any solution? Can the problem be in java, mozilla,
etc...?

I've tryed to change the macromedia Flash version which comes with Warty
by the one by firefox, but it doesn't solve my problem.