Broken WebGUI

[Grosrem]

Hi,
I have a Pfsense on my network since something like 5 or 6 months, and it has been alright until this morning.
Now when I connect I see something like that instead of the classic WebUI
:

The other part of the problem is that now I can't do any modification on the configuration.
I always get message like this one (not always the same):
Warning: Invalid argument supplied for foreach() in /etc/inc/util.inc on line 317 Warning: Invalid argument supplied for foreach() in /etc/inc/util.inc on line 317 Warning: Invalid argument supplied for foreach() in /etc/inc/util.inc on line 317

I haven't tried to reboot the box yet because it's quite in production, so it's not that easy.
Has anyone an idea about this problem.
Thanks.