function actions () {
	document.getElementById('header_topnav').getElementsByTagName('li')[0].style.border = '0';
	document.getElementById('header_nav').getElementsByTagName('li')[0].style.border = '0';
	
	if(l & r) {
		var l = document.getElementById('sub_main').offsetHeight;
		var r = document.getElementById('sub_sidebar').offsetHeight;
		
		if ( l > r ) {
			document.getElementById('sub_sidebar').style.height = l + 'px';
		} else {
			document.getElementById('sub_main').style.height = r + 'px';
		}
		
		if ( document.getElementById('sub_nav') ) {
			document.getElementById('sub_nav').getElementsByTagName('li')[0].style.border = '0';
		}
	}
}

function toggleButtonOn(id) {
	document.getElementById(id).src = 'img/'+ id + '_2.gif';
}

function toggleButtonOff(id) {
	document.getElementById(id).src = 'img/'+ id + '_1.gif';
}

sfHover = function() {
	var sfEls = document.getElementById("header_topnav").getElementsByTagName("LI");
	for (var i=0; i<sfEls.length; i++) {
		sfEls[i].onmouseover=function() {
			this.className+=" sfhover";
		}
		sfEls[i].onmouseout=function() {
			this.className=this.className.replace(new RegExp(" sfhover\\b"), "");
		}
	}
}
if (window.attachEvent) window.attachEvent("onload", sfHover);

sfHover2 = function() {
	var sfEls = document.getElementById("header_nav").getElementsByTagName("LI");
	for (var i=0; i<sfEls.length; i++) {
		sfEls[i].onmouseover=function() {
			this.className+=" sfhover2";
		}
		sfEls[i].onmouseout=function() {
			this.className=this.className.replace(new RegExp(" sfhover2\\b"), "");
		}
	}
}
if (window.attachEvent) window.attachEvent("onload", sfHover2);

function displayImage ( p_image ) {
	URL = "displayimage.php?img=" + p_image;
	window.open (URL,"Afbeelding","width=200,height=200,resizable=yes,scrollbars=auto,toolbar=no,location=no,directories=no,status=no,menubar=no,copyhistory=no");
}