How do you rotate the sky box?

Or is that possible? I have been trying to tweak it in in skyBox.cpp, but it turns to black whenever I try to put in rotation code. Here's my code:

mat.set( EulerF( 0.0, 0.0, mRotatingAng ) );
mRotatingAng += 0.5f;

if (mRotatingAng > TWOPI)
{
mRotatingAng = 0;
}

mat.setColumn(3,pos);

sgData.objTrans = mat;

mMatrixSet->restoreSceneViewProjection();
mMatrixSet->setWorld( mat );