var W3CDOM = (document.createElement && document.getElementsByTagName);
	var mouseOvers = new Array();
	var mouseOuts = new Array();
	
	function init(){
		if (!W3CDOM) return;
		createMouseOvers('cat_menu',num);

	}
	
	function createMouseOvers(the_id,num){
		var nav = document.getElementById(the_id);
		var imgs = nav.getElementsByTagName('img');
		for (var i=0;i<imgs.length;i++)
		{
			imgs[i].onmouseover = mouseGoesOver;
			imgs[i].onmouseout = mouseGoesOut;
			var suffix = imgs[i].src.substring(imgs[i].src.lastIndexOf('.'));
			mouseOuts[i] = new Image();
			mouseOuts[i].src = imgs[i].src;
			mouseOvers[i] = new Image();
			mouseOvers[i].src = imgs[i].src.substring(0,imgs[i].src.lastIndexOf('.')) + "_over" + suffix;
			imgs[i].number = i;
			if(i==num){
				mouseOuts[i].src = mouseOvers[i].src;
				imgs[i].src = mouseOvers[i].src;
			}
				
		}
	}

	function mouseGoesOver(){
		this.src = mouseOvers[this.number].src;
	}
	
	function mouseGoesOut(){
		this.src = mouseOuts[this.number].src;
	}

  function checkform(form){
    missing = '';
    for(i=0; i<form.length; i++){
      name = form.elements[i].name;
      if(name.indexOf('*') == 0){
        if(form.elements[i].value == ''){
          missing += name.substr(1) + ',';
        }
      }
    }
    if(missing != ''){
      alert('Vul aub de volgende velden in: '+missing);
      return false;
    }
    return true;
  }