Hi ShapeShifter. Thanks for reply.
ShapeShifter:
On your Mini, it looks like the SD card is mounted as sdb1. Can you access the SD card using sdb1 instead of sd?
I don't think that the sdb1 is the SD card since, as I wrote, I get the exact same printout even after removing the dogUSB and rebooting. Anyways, I tried as you said to mount it to sd. It wont let me using openWRT, but the web-interface made it possible, but still, I cannot see the 'arduino/www' folders that I've put on the SD. And the same warning when uploading the sketch.
Yes, a linux-expert tip here would be great. Or if anyone knows the smartass-engineer that made the dogUSB? 
Note: I have tried to create a user on the linino forum, but I never received any confirmation mail. I just tried to call doghunter in Switzerland. A woman answered, and I asked for technical support. She told me to wait, and soon hung up. When I tried to call back, they won't answer. And the number for the office in Boston is not in use.. 