I think the camouflage is probably due to the fact that these craft are expected to fight and defend the coastal areas, islands, and fjords of the Norwegian Coastline. They are not meant for deep sea fleet engagements.

http://en.wikipedia.org/wiki/Skjold-class_corvette

This navy craft is not painted in the traditional navy-grey colour,, the paintwork on this craft looks more like a 'camouflage for on-land' ..... that's much interesting, and I wonder what's the reason for that kind of paintwork !?