At exactly 7pm local time tonight (9am GMT/UTC) my (Virtualbox on Ubuntu) UT box froze. CPU usage 0%, blank screen, no disk usage.
After waiting the better part of an hour (nothing changed) I rebooted the box, and cancelled the Splashy screen, so I could see if it froze on boot.
I have no idea what version of Untangle it is currently. I have it on auto-update, so would *assume* it is (or close to) the latest version.
Here is where it is freezing on boot:
http://dl.dropbox.com/u/9818705/UT%20-%20frozen.PNG