<!--
	var httpRequest;
	var element;
	var queue = new Array();
	var navigation = new Array("nav_welcome","nav_requirements","nav_tutorial","nav_about");
	var tabs = new Array("tab_packages", "tab_configuration","tab_customizing","tab_start");

	function error(message)
	{
		document.write("<div style='border:2px solid red;color:red;font-size:2em'>ERROR</div>");
		document.write("<div style='border:2px solid red;color:red;font-size:1em'>"+message+"</div>");
	}

	function page(activeID, pageURL)
	{
		for (i=0;i<navigation.length;i++)
			document.getElementById(navigation[i]).className ='';
		document.getElementById(activeID).className ='active';
		set('main', pageURL);
	}

	function tab(activeTabId, url)
	{
		for (i=0;i<tabs.length;i++)
		{
			var elem = document.getElementById(tabs[i]);
			if (elem!=null)
				elem.className ='';
		}
		var activeTab = document.getElementById(activeTabId);
		if (activeTab != null)
			activeTab.className ='active';
		set('tab',url);	
	}

	function set(elementID, url)
	{
       //alert("set('"+elementID+","+url+"):"+httpRequest);
		if(httpRequest !=null && (httpRequest.readyState == 1 || httpRequest.readyState == 2 || httpRequest.readyState == 3)) {

         queueLength = queue.length; 
         queue[queue.length] = new Object(); 
         queue[queueLength].elementID = elementID; 
         queue[queueLength].url = url;
//alert("...enqueuing("+queue[0].elementID+","+queue[0].url+")");
		  return;      
      	}
		element = document.getElementById(elementID);
		if (window.ActiveXObject) // for IE 
		{ 
    		httpRequest = new ActiveXObject("Microsoft.XMLHTTP"); 
		} 
		else if (window.XMLHttpRequest) // for other browsers 
		{ 

    		httpRequest = new XMLHttpRequest(); 
		}
		var fullURL = document.URL.substring(0,document.URL.lastIndexOf("/")+1)+url;
		//document.write(fullURL);
		httpRequest.open("GET", fullURL, true);
		//httpRequest.onreadystatechange = function() {processRequest(); } ; 

		httpRequest.onreadystatechange = function () { 
            if(httpRequest.readyState == 4) { 
				 processRequest();
               if(queue.length != 0) { 
//alert("unqueue("+queue[0].elementID+","+queue[0].url+")");
                  set(queue[0].elementID, queue[0].url); 
                  queue.shift(); 
               } 
            } 
         };
		try {
			httpRequest.send(null);
		}
		catch (e) {
			error("page not found:<br>\n"+fullURL);
		}
	}

	/** 
    * This is the call back method 
    * If the call is completed when the readyState is 4 
    * and if the HTTP is successfull when the status is 200 
    * update the profileSection DIV 
    */ 
    function processRequest() 
    { 
        if (httpRequest.readyState == 4) 
        { 
			try{
            	var responseText = httpRequest.responseText;
				element.innerHTML=responseText; 
			}
			catch(e) 
          { 
        		error("Error loading page\n"+ httpRequest.status +":"+ httpRequest.statusText+" "+e); 
           } 
        } 
    } 


//-->