function switchImage(resource,way){
	if(resource != this.locatie){
		if(way == "over"){
			document[resource].src = 'img/bt_'+resource+'_a.gif';
		}
		if(way == "out"){
			document[resource].src = 'img/bt_'+resource+'.gif';
		}
	}
}

function setLocation(loc){
	if(loc != 'undefined'){
		document.location.href = '?pagina='+loc;
		this.locatie = loc;
	}
}