function changeSonitecMenus(i) {

	// Disallow certain selections. Notify customer if they select bad combination.

	// VARIABLES:
	// The input that sent us here.
	var sender = i.name;
	// The form we're controlling.
	var f = i.form;
	// The currently selected thickness (value).
	var thickness = f.thickness.options[f.thickness.selectedIndex].value;
	// The currently selected pattern (value).
	var pattern = f.pattern.options[f.pattern.selectedIndex].value;
	// The size menu and its current selection.
	var size_menu = f.size;
	var size = size_menu.options[size_menu.selectedIndex].value;
	// The color menu and its current selection (value).
	var color_menu = f.color;
	var color = color_menu.options[color_menu.selectedIndex].value;

	// 12x12x1 piece can only be 2" wedge in dark gray/gray.
	if (size == '12x12x1') {
		if ((thickness != 2) || (pattern != 'wedge') || ((color != 'Dark Gray') && (color != 'Gray'))) {
			var available_color = 'Dark Gray';
			if (f.name == 'sonitecplus_form') available_color = 'Gray';
			alert ('The single 12" x 12" piece is only available as a ' + available_color + ' 2" wedge.');
			size_menu.selectedIndex = 1;
		}

	// 77x77x1 piece can only be in dark gray color.
	} else if (size == '77x77x1') {
		if (color != 'Dark Gray') {
			var available_color = 'Dark Gray';
			alert ('The 77" x 77" sheet is only available in ' + available_color + '.');
			size_menu.selectedIndex = 4;
		}
	}

	// End.
	return;
}