if (document.images)

	{
	knop_01on = new Image(); 
	knop_01on.src = "images/buttons/knop_19_over.gif"; 

	knop_02on = new Image();
	knop_02on.src = "images/button_over.gif";

	knop_03on = new Image();
	knop_03on.src = "images/button_over.gif";

	knop_04on = new Image();
	knop_04on.src = "images/button_over.gif";

	knop_05on = new Image();
	knop_05on.src = "images/buttons/knop_16_over.gif";

	knop_06on = new Image();
	knop_06on.src = "images/button_over.gif";

	knop_07on = new Image();
	knop_07on.src = "images/button_over.gif";

	knop_08on = new Image();
	knop_08on.src = "images/button_over.gif";

	knop_09on = new Image();
	knop_09on.src = "images/button_over.gif";

	knop_10on = new Image();
	knop_10on.src = "images/buttons/knop_23_over.gif";

	knop_11on = new Image();
	knop_11on.src = "images/button_over.gif";

	knop_12on = new Image();
	knop_12on.src = "images/buttons/knop_56_over.gif";

	knop_13on = new Image();
	knop_13on.src = "images/buttons/knop_57_over.gif";

	knop_14on = new Image();
	knop_14on.src = "images/button_over.gif";

	knop_15on = new Image();
	knop_15on.src = "images/buttons/knop_17_over.gif";

	knop_16on = new Image();
	knop_16on.src = "images/button_over.gif";

	knop_17on = new Image();
	knop_17on.src = "images/button_over.gif";

	knop_18on = new Image();
	knop_18on.src = "images/button_over.gif";

	knop_19on = new Image();
	knop_19on.src = "images/buttons/knop_18_over.gif";

	knop_20on = new Image();
	knop_20on.src = "images/button_over.gif";

	knop_21on = new Image();
	knop_21on.src = "images/button_over.gif";

	knop_22on = new Image();
	knop_22on.src = "images/button_over.gif";

	knop_23on = new Image();
	knop_23on.src = "images/button_over.gif";

	knop_24on = new Image();
	knop_24on.src = "images/buttons/knop_20_over.gif";

	knop_25on = new Image();
	knop_25on.src = "images/button_over.gif";

	knop_26on = new Image();
	knop_26on.src = "images/button_over.gif";

	knop_27on = new Image();
	knop_27on.src = "images/button_over.gif";

	knop_28on = new Image();
	knop_28on.src = "images/buttons/knop_15_over.gif";


	knop_01off = new Image(); 
	knop_01off.src = "images/buttons/knop_19.gif";

	knop_02off = new Image(); 
	knop_02off.src = "images/button.gif";

	knop_03off = new Image(); 
	knop_03off.src = "images/button.gif";

	knop_04off = new Image(); 
	knop_04off.src = "images/button.gif";

	knop_05off = new Image(); 
	knop_05off.src = "images/buttons/knop_16.gif";

	knop_06off = new Image(); 
	knop_06off.src = "images/button.gif";

	knop_07off = new Image(); 
	knop_07off.src = "images/button.gif";

	knop_08off = new Image(); 
	knop_08off.src = "images/button.gif";

	knop_09off = new Image(); 
	knop_09off.src = "images/button.gif";

	knop_10off = new Image(); 
	knop_10off.src = "images/buttons/knop_23.gif";

	knop_11off = new Image(); 
	knop_11off.src = "images/button.gif";

	knop_12off = new Image(); 
	knop_12off.src = "images/buttons/knop_56.gif";

	knop_13off = new Image(); 
	knop_13off.src = "images/buttons/knop_57_over.gif";

	knop_14off = new Image(); 
	knop_14off.src = "images/button.gif";

	knop_15off = new Image(); 
	knop_15off.src = "images/buttons/knop_17.gif";

	knop_16off = new Image(); 
	knop_16off.src = "images/button.gif";

	knop_17off = new Image(); 
	knop_17off.src = "images/button.gif";

	knop_18off = new Image(); 
	knop_18off.src = "images/button.gif";

	knop_19off = new Image(); 
	knop_19off.src = "images/buttons/knop_18.gif";

	knop_20off = new Image(); 
	knop_20off.src = "images/button.gif";

	knop_21off = new Image(); 
	knop_21off.src = "images/button.gif";

	knop_22off = new Image(); 
	knop_22off.src = "images/button.gif";

	knop_23off = new Image(); 
	knop_23off.src = "images/button.gif";

	knop_24off = new Image(); 
	knop_24off.src = "images/buttons/knop_20.gif";

	knop_25off = new Image(); 
	knop_25off.src = "images/button.gif";

	knop_26off = new Image(); 
	knop_26off.src = "images/button.gif";

	knop_27off = new Image(); 
	knop_27off.src = "images/button.gif";

	knop_28off = new Image(); 
	knop_28off.src = "images/buttons/knop_15.gif";

	}

function imgon(imgName)

	{
	if (document.images)
		{
		document[imgName].src = eval(imgName + "on").src;
		}
	}

function imgoff(imgName)

	{
	if (document.images)
		{
		document[imgName].src = eval(imgName + "off").src;
		}
	}