if (document.images) {
		img_head = new Array();
		img_head_off = new Array();
		
		img_head[1] = new Image();
		img_head[1].src ="img/menu_jaarverslag_over.gif";  
		img_head_off[1] = new Image();
		img_head_off[1].src ="img/menu_jaarverslag.gif";
		
		img_head[2] = new Image();
		img_head[2].src ="img/menu_jaarmagazine_over.gif";  
		img_head_off[2] = new Image();
		img_head_off[2].src ="img/menu_jaarmagazine.gif";
		
		img_head[3] = new Image();
		img_head[3].src ="img/menu_downloads_over.gif";  
		img_head_off[3] = new Image();
		img_head_off[3].src ="img/menu_downloads.gif";
	}
	
	function swap_head_img_on(nr) {
		if (document.images) {
			imgOn = img_head[nr].src;
			document.getElementById("img_head_"+nr).src= imgOn;	
		}
	}
	
	function swap_head_img_off(nr) {
		if (document.images) {
			imgOff = img_head_off[nr].src;
			document.getElementById("img_head_"+nr).src= imgOff;
		}
	}