Replaced by drop out (I had a spare one in my bike bag) and fixed my derailleur with a random piece of plastic and ducttape. Maybe not the most solid way to do it but didn't have much choice since I needed a 5th race to get a shot at a good overall place.
The race didn't go very well and I did have some more mechanical problems a long the way. Finished in 19th place which got me an 14th place overall.
http://www.mtbocamp.dk/2012/results5.htm
http://www.mtbocamp.dk/2012/overall6.htm