Qt: Transformed: driver not found

holger
Hello
I created with QtCreator a test GUI for the mini6410 (only a button and a
label). But when I would run it, I get the following:

./guitest -qws
Transformed: driver not found
Aborted

env | grep DISPLAY on the mini says:
QWS_DISPLAY=Transformed:Rot0:0


What have I to do an the mini to get the program working?