As subject, whenevere I start in OB after some time, generally less than 10 minutes, the pc hangs and the only thing possible is to manually reset. When say hang I mean that the screen, windows, panel, everything is blocked and doesn't respond to the keyboard or the mouse. The only thing that still move is the mouse cursor, but clicking is completely ineffective.

I'm using Archlinux 0.7.2, kernel 2.6.18-emission (but the freeze happens also with 2.6.17-beyond and 2.6.18 vanilla), OpenBox 3.3.1, Xorg 7.1.
At boot the only apps loaded are conky, yakuake, pypanel, mrxvt, rox-filer and firefox (each one at the latest version).

Unfortunately is hardly reproducible, it can happen after 2 min or 15 min after the starting of OB; I think that it's related with OB because the pc run flawlessy for hours in KDE, from the terminal, in Ubuntu with Gnome and in WinXp  (so this rule out an hardware related problem).

If you need more info I'll happily provide it.