Index: /trunk/src/VBox/Additions/WINNT/Graphics/Display/drv.c
===================================================================
--- /trunk/src/VBox/Additions/WINNT/Graphics/Display/drv.c	(revision 35502)
+++ /trunk/src/VBox/Additions/WINNT/Graphics/Display/drv.c	(revision 35503)
@@ -195,6 +195,8 @@
     DISPDBG((1, "%s\n", __FUNCTION__));
 
-    /* Just forward this to the software engine. */
-    rc = EngDitherColor(((PPDEV)dhpdev)->hdevEng, iMode, rgb, pul);
+    /* There is no EngDitherColor on NT4, so take the easy path and tell the graphics
+     * engine to create a halftone approximation.
+     */
+    rc = DCR_HALFTONE;
 
     return rc;