Smoke effect extrusion

Hi thereI have a question regarding the extrusion part of the smoke effects in FS.The smoke effect is made up of two parts; type 19 sprites and type 21 extrusions. As far as I know the extrusion is created perpendicular to the surface of the earth (like a banner) by default. Alternatively it is created parallel to the surface by setting GroundNormal=1 in the .fx file.Does anyone know wether it is possible to have the extrusion remain parrallel to the wings of the airplane (banking and rolling with the plane)?Hope my question is clear enough!Marcel