Just got off the phone with our salesmanager in Germany. Apparently, one of network adapters in our firewall got nuked due to power fluctuations last night.
I asked him to fetch a shiny new 10/100 network adapter, and guided him over the phone how to change it. Remarkably it went smooth, and now everything is working again..
I had been considering leaving *real fast* for Germany, but I guess, sometimes you just need to have a little faith in our sales staff ;)