Bug of displaying in 3D Viewer on WNT

Bug reproducing
Start AISViewer on WNT on KAS:dev:ros
Create box a 100 100 100
vinit
vdisplay a
Box is displayed by default in wire frame mode
Click to 3D Viewer.
Box is displayed in hidden line mode.

Select shaded mode of box displaying.
Box is displayed in shaded mode.

Click to 3D Viewer.
Box is displayed in hidden line mode.

Try to rotate box. Box is displayed in shaded mode during rotating

Effect does not appear on SUN station