Antonio, can you add this code to printdc.c? Maybe it is for some people useful.
HB_FUNC( ISCOLORPRINTER )
{
LPDEVMODE lpDevMode;
PrinterInit();
lpDevMode = (LPDEVMODE) GlobalLock( pd.hDevMode );
hb_retl( lpDevMode->dmColor == DMCOLOR_COLOR );
GlobalUnlock( pd.hDevMode );
}