Jørn Dahl-Stamnes writes:
As you can se, no reason. I called them and first they was not sure why I
got this message. After some checking they told me that they wanted to fax
my bank to verify my card. Is this normal behaviour?

It doesn't surprise me.

This is the 4th time I order stuff from them, using the same credit card.
Maybe it is due to the large value (~ $6000).

That would be a good reason.