RotMatrix InitFrom2Vectors vectors wrong?

Hi,

I'm using the function RotMatrix :: InitFrom2Vectors( DVec3dCR xVector, DVec3dCR yVector) to initialise a Rotation Matrix for a new ACS.

RotMatrix acsRot;
DVec3d xVector, yVector;

xVector.Init(0, 1, 0);
yVector.Init(0, 0, 1);

acsRot.InitFrom2Vectors(xVector, yVector);

My xVector points in the y-Direction and my yVector points in the x-Direction of the new ACS. So I have to use the function like this:

InitFrom2Vectors(yVector, xVector)

Is someone able to proof, if I did sth. wrong, or if this is a generell problem.

Windows 10, Microstation Connect, C++, VS2017